Beefing up A500 overdrive

I just need some information as to start setting up the ducks. I’m a bit deficient in this area. I’ve been running a manual 4spd for decades. I’m just starting in with automatics.
same here, gatherings of informational stages. I only wanna do it once, and pretty much made up my mind on the 500/42 due to less parasitic loss, not needing a unit to handle big hp/tq numbers and the fact that I can mate it to a G3 down the line if I so choose.

I just want to build the best possible piece and get all the parameters right the first time around.