That should be a very nice start! I think getting the car into the back in going to be the most challenging part. Can you make an "extension" for the lift gate that would do it? That would be my first route to peruse.
Here is the list of builds I was mentioning, look for the uhaul ones. Although the 4x4 guys have less ramp/breakover angle issues to deal with.
PBB Tow Rig/Trailer Build Threads - Pirate4x4.Com : 4x4 and Off-Road Forum