Blue Brick

You said you are going to run an E body in road racing and the A body is for autocross?
I not that familiar with any of this although I think understand the basic differences.
My question is why not run the A body in road racing?
The A body should do everything the E body does and be lighter?
Did the Green Brick not run road racing courses?
I can only guess there are some restrictions in modification that can be done associated with rules about classes.

Either way vice versa.

But if you are get real competitive with auto-cross, whatever the car, the refined setup would typically need some changes for a track day car. Especially if it was a fast track without a lot of tight turns. And you wouldn’t run/waste a supersoft autocross tire on the track.