Is it possible to remove the body off of a 70 Chevelle without removing the carpet and interior??

I would think so if you can get the body mount bolts loose. If it's a console shifter, that needs to be disconnected. Everything else is outside the cab I think. BUT if the floors aren't solid, you'll have to pull the seats anyway, eventually. It only takes about 30mins to pull the seats and carpet. They're the least of the effort.

Don't forget your emergency brake cable and all linkages from the dash to the engine compartment plus your fuel tank connections.