Dude, check the front inner wings for ripples and as someone else said check the rear wheel sit the same distance from the arches each side as the rear beams bend easily. A lot of old saphs suffer from rotten chassis rails – check where the rear beam bolts up etc.

I’ve seen a few dogs in my time...

Not wishing to put you off and they are so much fun but finding out you have a bent or rotten car can wipe the smile off of your face! Totally agree with the north yorks rs guy, ask plenty of questions - good luck