I'd first start with building up the engine and tranny , no sense in having power the vehicle cannot handle.

I'd invest in a tourque converter, tranny cooler & oil cooler, rods & pistons, bore out the intake runners and throttle body. Super charger, exhaust and intake, fuel pressure riser (fpr). NOS to add the icing on the cake if you so desire!

Then fine tune it on a dyno to get it all in harmony

A lot of this work will be custom no doubt and I imagine will cost some bank but i think with the $$$ you're considering it is not that far out of reach.

I don't care what any ones says here ... folks don't have enough miles tuned in this fashion to give a realistic reality of this motor & tranny with the mods most have now. I foresee problems with these vehicles later down the line after many years and miles with more HP's under the hood and harsher driving conditions then what it was designed for! I'll put money on it