SBC 350 to 383 conversion

Hi all, been looken around here for a while now, great info from a lot of people here. Anywayse, looking to upgrade again, a few years back I put a 5.7 multiport fi suburban engin into my s-10 and it was fun for a while. Now my question is, can I make the 350 into a 383 and keep mpfi? 97 was the last year for prom chips, I had the dealer back home reflash my 4.3l ecu (same p/n as 350's) to a vin R 350. Does the computer even need flashed or will the o2's pick up on the lean and compensate for it? currently I would pass emmisions if I ever needed to and when i pop the hood it looks like gm put it there, i dont wanna go to a toilet bowl if i can help it.
Thanks in advance
Doug

Guys do it on vettes and F bodies all the time..I don't see why your situation would be any different..You would have to re tune for optimum performance but that's all..

who can do the flash? is it something the dealer can do, or a speed shop or is this something that jet needs me to mail my ecu to them, wait and have it mailed back to me?