VMware Fusion help with importing 350GB Time Machine backup using migration assistant into...

I am running VM Ware on Mountain Lion. I am also running Mountain Lion inside my virtual machine. I am trying to import a time machine backup of my previous snow leopard drive into my virtual machine. I did not want to import this into my new drive because I am starting fresh and trying to clean up, but I would still like to have my old SL drive running withing VM Ware to help with the transition. It sure beats restarting over and over again for time I need to open applications.

Anyway, here is the problem I am having and cannot seem to get past this hurdle. When I open migration assistant and choose my time machine backup of snow leopard everything works fine until it finishes calculating the size. I deselected all the files and folder I possibly can which leaves 350GB. Even with every single folder deselcted it still give an insufficient storage error I have already resized the VMware drive to 400GB which is more than enough. In my real machine under Finder>Get Info it shows it as 400GB, but within the virtual machine it is only showing the Mac HD to be 40GB which won't allow migration assistant to import the backup due to insuffient storage.

I have a Mac Pro with tons of disk space so I have a ton of free space to allocate but I have tried everything I can think of but came up blank. Sorry if my explanation was overly verbose or confusing but I wanted to give as much detail as possible. Haven't really fiddled with the settings in VM Ware in a while so I must be missing something. 

So, how do you import 350GB worth of files from a time machine backup with migration assistant without getting an error that there is not enough remaining space? And again, I have already resized the disk to 400GB that shows as 400GB on my real machine but only as 40GB inside the VM Ware Mac HD. I also have Parallels if that is easier to do what I am trying to accomplish. 

Thanks for the reply. I have 4 internal disks and Snow Leopard still boots up just fine from that disk. No, it isn't about PPC apps or rosetta, mainly about Rapidweaver. On Snow leopard I have Rapidweaver 4 installed and on my new clean install of ML I have RW5 installed. I was having some problems opening and editing some website files with 5, crashing and other glitches. Also a few more things like some bookmarks from web browsers, emails, and just the ability to have both working at the same time so I can import just what I want slowly over time without guessing at folders and files. I got a little sloppy with my organization the last few years so it is a real mess which I want to avoid on my new ML drive. But I still want to import all the good stuff and organize it carefully so the ability to have my old computer run side by side my brand new clean install seemed like a simple thing to do until I ran into this dilemma.

I also have Parallels if that is easier to accomplish. What I am thinking of trying and correct me if I am wrong, is to just copy a folder with a lot of data, like 10GB or more and keep duplicating it which should expand the dynamic disk from 40GB to the logical size actually showing in the finder of 400GB. Then when that is finished just delete those files and try the migration assistant. It is a dynamically expanding disk after all unless 40GB is the absolute maximum it will expand. 

I am surprised this was an issue since I wold think many other people would want this ability to essentially run their old Mac OS along side a clean new install especially if you have dual monitors like me. Importing it directly in the past is what made my SL so slow and full of junk so I wanted to take the extra time to start fresh. Importing photos, videos, or audio files is easy enough, but a lot of what I want to do requires seeing my old user account up and running. 

I will keep you up to date and see if I can get a fix. I actually deselected every single file and folder possible under migration assistant and it still was too large. And I do mean every single thing you can deselect. I hate to try and go through all those thousands of folders being a sleuth. Probably email attachments, app support folders, and many others that would take a lot of time to find. 

Right now I am trying the split into 2GB file option and VM Ware has been rebuilding the disk for about an hour. Pre-Allocate to 400GB was already selected and used to create the disk at 400GB. I am not worried about breaking the virtual disk since I have a back up so I am free to experiment. I am tenacious so I will figure this out one way or the other if it is possible. If I do I will post the results because this could actually be extremely useful to have an old drive or even different Mac running inside a VM. Importing and migration can work well if you are just going from OS X 7 to 8 for example, but I had files, apps, and God only knows what going back from Mac OS 8.5 and maybe even earlier. So I really wanted a completely fresh start and to import very slowly to avoid issues. And the good news is that it worked, pretty much every app opens faster than I can even release the mouse click button whereas before it took anywhere from 2 to 15 seconds  for some apps to open which shouldn't happen on a Mac Pro loaded with Ram and very fast hard drives. 

I just solved the problem! And this is actually a pretty big deal because experts at the VM Ware Fusion website and many other forums told me it was impossible. 

So here is the guide to running Mountain Lion in VM Ware Fusion or Parallels with a partition larger than 40GB and allows you to import an old user account from Tiger, Snow Leopard, Lion, etc..

1) Make sure to shut down Mountain Lion in VM

2) Under VM settings expand hard drive to whatever size you like

3) You will need either a disk image or an actual DVD of mountain lion, mount that in your VM and choose it as start up. After rebooting open disk utility and partition Mac HD. Instead of only showing the 40GB limit it shold now show the size you created from step 2. Close disk utility and install Mountain Lion as normal. Reboot and unmount disk image. 

4) You now have a virtual Mountain Lion with whatever hard disk size you chose.

5) Open migration assistant and do your time machine back up as normal from previous systems.

The reason you might want to do this are many. In my case I wanted to have my old Snow Leopard user account open and running on my second monitor since I just did a fresh install on my Mac Pro. It is easy to import audio, photos, videos but there was a lot of other things I want to take my time bringinging over. There are also many cases where I needed to open up an app and view settings. Now I have my old machine essentially running at the same time as my new install side by side which is fantastic. 

Only Snow Leopard server is allowed on VM Ware not the client. But since Lion the regular client version of OS X is allowed.

What they meant was impossible  was resizing the main boot disk first created so that it is seen as anything larger than 40GB. All I got was a lot of crap asking me why I wanted to do this, or it is possible on Windows but not on OS X. Many reasons why I couldn't or shouldn't but no real help. 

But all I had to do was re-partition the drive with disk utility. I guess that escaped me at first because I thought that was too easy and obvious. But it worked and I am looking forward to being able to have access to my old account until the transition is fully complete.