If the Weber carbs are missing, an exhaust valve and an inlet valve will be open, so water will get in to 2 bores. The engine does not turn over. Sounds like corrosion in 2 bores at least. £700 for new liners. Been there, done that.
Respray, re-trim, new dashboard needed MISSING ASHTRAY, no servos, missing spare wheel, rear anti-roll bar, non-standard front anti-roll bar, adjustable rear bottom arms, driveshaft hitting the gear change rod, strange water pump and drive pulleys, and a strange tube down the right rear engine compartment that looks like a roll over bar. It sticks out where the petrol filler caps are, horrible and useless.