Just a thought, but when I have the room for it (when I build my shop). I'm going to look for a used Frame Rack. The type used for frame repair. The body shop that my dad runs has a Kansas Jack setup. You can basically clamp the rocker pinch welds wherever you want the car to sit and build the frame to the car. They are typically a beefy setup and you would also have the capability to pull the frame or unibody if it needed it (previous damage etc.) You are probably looking at $5K or more for a decent used one and 2 or 3 times that much for a nice one.
Here is an ebay link to one like I'm talking about - this one is pricey but they can be found for cheaper.
http://cgi.ebay.com/ebaymotors/KANSA...02774738QQrdZ1