Yes, I would build the TR8 again but really now (after racing for a while) only for one reason: prodigious torque. The car has an advantage because of that.

The thrill of racing your favorite marque goes away quickly, trust me, unless there is some light at the end of the tunnel.

I'm not telling you building the BGT is insane, or not to do it. If that is what you really, really want to do, do it, because you have to really want it or you won't race. The problem as I see it with the BGT that the JH (light weight, decent power), the Opel (really good aero and decent power/weight for IT and the TR8 (gods of torque and decent handling) don't have is one area where the car really shines. You can make a B handle, see Prod cars, but I don't know if that will require doing things you can't do in IT.

BUt the the big problem as I see is is power out of the 1.8 in IT trim. I just don't know how you are going to get the power you need out of that motor with the Stromberg, and no real head work or compression bump allowed.