what sort of HP would i have with a 75-100 shot os NOS , full 3-in exaust, and what sort of things do you suggest for more power?

BTW 3.08 rear posi and 700r4 trany with a LG4...lol

Well you will have 75 to 100 more than you started with. I would not even consider the juice unless you have a full exhaust and a upgraded fuel system.

If you actually use NOS the brand expect to see around 75% of that at the wheels.

Fuel system is probably okay, not sure on LG4 specifications. Exhaust is something that should already be done.