I am trying to hunt down a good 745 engine and think I might have found one that had been swapped to another car (with a later head). It seems to have the 745 manifold and the block is printed 3.0/3.3 (I think this was right for early turbo?). Any way I can tell if it is original 745 from numbers or features on outside of block?

thanks

Just trying to figure this really strange set up I found with block as described, 86 head, Korman intake & triple Mikunis with large aftermarket air box on end. Also has 745 exhaust manifold with large turbo and intercooler above valve cover. Can't figure out if it was a tuner job or someone just throwing parts together.