selection of TBI components for 383 Chevy

[sfg]

I'm building a mild-mannered 383 SBC for torque to repower my '87
Blazer.  Would like the groups suggestions on TBI components. I'll reuse
GM ECU. I'm devoted DIYer and the Howell prices put me in sticker shock.
1. reprogrammed chip set....DIY or off the shelf?  is it really needed?
   (what happened to recent thread on hacking GM ECU codes?)
2. Throttle Body.... 2bbl or 4bbl? Holley? BG? OEM? is 4bbl overkill?
3. inlet manifold.... Holley, Edelbrock, OEM, other?
Thanks, Steve