Forced Induction on a TPI 350

Ok, so heres the Deal. Im going to be getting a TPI setup for my target 350. 26# Injectors, Speed/Density. I want to twin turbo it, Ive found some good front placing Turbo Manifolds for SBC's with T3/T4 Flanges and some Garrett T3/T4 Turbos for relatively cheap. Now, I could do them hot air for now, just low boost, nothing big yet, and once I can get the intercooler piped up and mounted effeciently, I can turn it up little by little. Anyways, the question ive got for you guys is how high of boost can I run with it just being hot air and without detonating my butt off? I dont want anything big for right now, but I do want some performance out of these once they reach effecient boost levels. I understand the car is heavy to begin with and that waiting for boost will be like running the car on piss and broken dreams at first (lol exaggerating exaggerating..) but regardless once it makes boost and gets to a good level I should be in alright territory..right?

btw the motor has 76cc heads and 8.5:1 C/R and im assuming cast pistons. The Valves are a WHOPPING (hah) 1.94/1.50 with a dinky hydraulic cam rolling in at .390/.410.

The main thing is, is it possible for me to run at low boost levels with proper fuel and air flow without an intercooler for a while? and If not would a 7" Tall, 4" Deep, and 16" Wide Bar and Fin Style intercooler do it well enough for me? And as such, would it be pheasible to just do the two charges into one pipe or should I have a custom dual inlet I/C made?

Bump? Should be buying my tpi and starting the project next week. Anyone know of any good honda sized intercoolers that would work behind my bumper? Need a dual inlet, possibly with the crossflow baffle