There was a local guy who had a Vega wagon with a 632 big block, a Powerglide, and a Dana 60 rear end. Car was fiberglass, lexan, 4-link with a cage and wheelie-bars. The dude owned a tranny shop. This car was stupid. Never could get it to go straight. Gee, I wonder why.
Vega's rule. You only see them at the tracks now. ( Especially in Texas )
I like the notchback Vega's. They are cool.
Vega's are made for small blocks. I almost traded my 70 Camaro SS for one back in the 80's, but the guy decided he wanted to just sell his Vega instead of trade it for something else. I was bummed. His vega was tubbed and pro-street`d. It was super sweet.
If you get a stock one, you will have to do all the chassis work.
( New rear-end, cage, frame connector links, wheel tubs, sheet metal, 4-link, etc. )
Best to find a roller, and drop your engine and trans in it.
Killer combo is a Ford9", 4-link, 4:56 gears, Powerglide tranny, and a 383 aluminum head roller motor. Add some spray, and say hello to 9-second 1/4 mile times.
You try a massive torquey big-block in it.... you better get used to seeing the retaining wall. ( or the guy in the next lane over! )