76/77 GT Liftback

Hey! I'm no tuner expert, which is why I came here. My friend has an old 76 or 77 Celica GT liftback. I know nothing about it other than that it's sat for years. I have no idea what a good deal on it would be, and I also need to know what kind of engine and transmission was used in those cars. I know it's an automatic transmission. The Rust spots on it are rather large, but most of them are surface rust. The exception is behind the back tire, where there are several spots that could be kicked out under the bumper. The other thing that I was wondering was the frame type, because I know that the back bumper, which I assume hooks to the frame, was falling off on one side because of rust. What I really want to know is:
-Would this be worth it
-What kind of engine(s) was used
-Drive wheels
-body construction

Thanx guys! This one could be my first project that I keep:smokin:

I'd pay less than $400 (if it ran), it has a 20r motor, rear drive.

thank god it's rear drive...that makes transmission work so much easier. So are these unibody?

I think so. :dunno:

If it is unibody, I'm screwed. The undercarriage is shot.