500-1000 whp? In a fwd? This old man is having a hard time from addressing you as son, but take these words of wisdom anyway. First off start out with a rwd platform and go with a V-8.
it can be done you need a Modded 4t65ehd the diff is supposed to be rated at 1000 at least the ZZP Unit is so Plus a 3800 can put out that power as well with mods like l32 rods forged pistons and alot of other supporting modifications.
search turbo monte timeline on youtube this is a 500whp but One of the turbo kits on ZZP is claimed to make up to 750 hp at the crank but yes many of the really fast w bodys are turbo LS4. but a 3800 can also be fast but its alot of $ & work
The cost of engine/head work, trans work with stall, chassis work, tires, tuning, beefy axles, etc. will give your hand cramps from writing the checks. I abide front drive cars because I really like my Electra for lazy cruising, but with the front wheels pulling I can't really enjoy it in the twisties, apply throttle tires scrubs. Maybe a moment of reflection is in order.