megasquirt fucking sucks. have you played with it? my god. lol i've been tuning for a while, and i can't figue that thing out....
you DONT need to go obd1.
you DONT need to go hondata.
pr3 will run your car.
pw0 will run your car.
what nitrous kit are you planning to use?
even if you get something with 2 maps... are you going ti switch chips, or have your laptop on for everytime you hit the juice? it's just not practical...
a zex kit or something with an NMU will be fine with the stock pr3 or pw0. so long as you keep it around the 65-ish shot area.
if you're looking for more than that, you want an AEM EMS, because it has a good nitrous control system that will completely bypass the NMU.