I would also try to keep the tub. First, you are building a race car so if constructed properly it is the cage that will protect you more than the tub. Consider that you are rebuilding a race-car not doing a concurs restoration.
But it does sound from that damage that you are describing that the car was hit from behind pretty hard.
I agree! This would would be were I would apply murphy's law. If you make this car show perfect and race it will get demo'ed! Seriously ,the cage if built corectly is going to put structure /rigidity into the car, and that's what will make it safe to race a flexey flier. My e12 has been sharked 3 times , only bruises were from the belts.( Im nota good driver) My concern though is what ruleset are you building to, can you really use the cage to tie up the chasis or are you stuck with a max , 6 point with two footwell, total of 8??
My cage ties into the rear subframe,the diff mount, all four shock towers, plus the normal 8pionts,, its a lot of bars, buts it really stiffened up a 30 year old BMW and is quite safe.
If you decide to look for another car , the guy I got mine from has another canidate, I could put you intouch with him , but its probally going to be more of the same??
good luck love your project
Bd #112