Hi Mike, sorry for delay to reply.It may be possible that the 302 has 500hp but I doubt it and would want to see a dyno or rolling road printout before I believe any hp claims. The engine may have good aluminium heads but the pics don't show this. There appears to be a 4 barrel carb which may be a Holley or Edelbrock.. From the size of the carb it does not appear to be a Holley double pumper. Ask the seller if they have a build sheet for the engine.
The inverted Porsche gearbox is most likely a G50 which is a good strong box.
As there are no suspension pics the uprights and brakes are unknown. The pics of the front and rear chassis are not available to see if it is GTD in origin.
The exhaust manifold usually fitted to GTD40s was a non crossover type and this car has a crossover manifold. The collectors are a bit basic. The seats originally fitted to GTD40s were leather seats with metal eyelets and were sat on metal frames. The seats in this car are original type fabric seats with eyelets. These items may have been fitted to make it more original looking.
The body is a replica style shape as it has the ridges at the top rear of the doors - original 40 bodies do not have this ridge.
The general condition looks good. It has the double front nostril panel. The rear window is plastic rather than glass as can be seen with attachment screws.
Cheers
Mike
The carburators are Holley (he told me).
Otherwise I have to say I'm impressed by your technical analysis.