LOL, I have the stroker 7MGTE, but if cost was no object, I'd go with the following.
LS7 based engine with custom pistons CR of 9:1
Everything coated where possible.
Two GT35 turbos on inconell custom manifolds.
Custom 6 speed trans and rear diff that would handle the power. (Think modified ford 9" rear like IJ did.)
Engine would be good for 1200hp or better on pump gas. (1500+ on race fuel.)
Car would be insane fast.
Really a AWD platform is needed for this amount of power to be usefull on the street or anywhere.
So, just give me a Veyron with the boost turned up so it makes 1200hp or so, and that would be fine.