The doors and the tail end remind me quite a bit of a '78 Chevy Monte Carlo.

yop, as i wrote before - engine from caddy, body from plastic and reminds 30's Cord (the front)

Clearly a custom. I don't read Czech, but some is decodable. "karosérie z plast?" bodywork in plastic (fibreglass?)? "motor Cadillac" Cadillac engine? "tvarem p?ipomíná vozy Cord ze 30.let" something from a 1930s Cord?

Looks like a custom one-off. The front lights remind me of an Econoline. I think it might have been a early '80s Seville by the taillights.

what should this be?? I found this on one czech site dedicated to cars as unidentified and am also wondering what should it be?

http://auta5p.car.cz/auta/neznam/neznam_01.htm
http://auta5p.car.cz/auta/neznam/neznam_02.htm

said to have a Cadillac engine and body from fiberglass..