I've done a ton of research- so now I'm really confused....

Best bang for the buck;
>For take-off; a hi-stall TC.
>For bottom end power; cylinder pressure.
>For everything else; bigger rear gears.
All the other things talked about require rpm to get the power; so if you're stuck with 2.73s and an 1800 stall, they are worthless until the rpm gets up. With 2.73s, 3500 is about 37 mph. I rest my case.
With a 3500 torque peak, your power peak will come in around 5000..... or 53mph.
With 2.73 gears your 4 bbl might start to open at 2500/26mph, but so what, the 2bbl was good to that at least, and it starts out at 1hp not 50.
Your 380hp engine will need a TC and gears anyway, so you might as well start there. The fastest way to blow an old tired engine is to start bolting go-fast stuff onto it; and so, is, IMO, a waste of time.