JD,
I'm building a kit now, and found a used G50 at a decent price, so that's what I'm going to stick with.
However, if I had it do over, I'd use what is called a V-drive, which allows you to use a conventional transmission (say from a Corvette), and then direct the power back to your rear differential via a custom drive shaft.
It sounds more complicated than it is, and moreover it can be done by anyone who fabricates drive shafts (which is common in amateur racing).
Try the website "Diablo Builders Forum" (
Index :: Kit c e n t r a l :: Lamborghini Diablo And Other Kit Car Builder's Support Group) and do a search function there on V-drive and you'll find it.
What is nice about the V-drives is they are easy to find (new or used), and accomodate very large amounts of horsepower without modification (typically 800 hp or more).
Basically what a V-drive does is redirect power from a spinning drive shaft back in the opposite direction.
So power from our Corvette transmission (which is pointing in the "wrong" direction for our GT40 kit) would be redirected to the differential in the rear.
You'd have to use an offset differential, but those are surprisingly easy to find (I like the one made by Quaife....nice piece of equipment).
(The reason the driveshaft is offset is because our engine in the exact middle of the car, so it needs to pass to the right or left of it)
Just an idea.
Chris