The 70-81 camaro is what years you want. they are 108" wheel base. i think the 88 camaros are 105" wheel base, could be mistaken. You can tie the frame together on the camaro. mine is on my car. JUst make sure your exhaust has enough ground clearnce to exit out the right side. let me no if you need some help with anything else on the camaro side.
the front running cars were midsize gm frams cut down to 108 wheelbase thats what franks sons salem car is (ie 77-88 impalas are the easiest to find they have the same gemonetry as a camaro use front spindles off of a big gm if you want 5x5 (i wouldnt advise using a metric chassis !)
I recommend calling Scott at Baker performance,he is one of the best at building these cars.He did a great job on mine.He can be reached at 330-773-0121.Also mine is for sale,77 monte carlo cut down to 108,has the factory motor set back,there for the firewall is in the stock position,best of everything,not cheap though. call frank at 216-509-2519
