tbi conversion questions?

[lofly'a]

i am in the starting stages of putting together a 454 for my 71 GMC swb and, planning on using feeding it with a tbi setup. here's what i have so far, a 1976 454 (haven't checked specs yet), a complete tbi setup from a 91 ck truck,
and a 91 454 throttle body from a 454SS.

my questions so far are, can i use the 91 harness, ecm, etc..... do a chip change and use the 454 throttle body? how much can i modify the internals of the engine (cam specs) without going outside of the ecm/tbi's control? i'm hoping for 300 to 325 hp which i'm told is conservative and do-able. i've also looked into Xtremefi's 750 cfm throttle body vs the stock 420 cfm unit and have been assured that the Xtremefi unit will operate properly, and support this build. My only other plans besides what mentioned are long-tube headers/exhaust, and a hotter spark.

I would appreciate all chime-ins and advice i can get.

[clay68c10]

There's some good info here.
http://www.tbichips.com/
I'm running the Edelbrock Performer cam in an older (70's) .030 over 454 with the stock 89 454 TBI setup and it runs like a champ. I'm right at 9:1 compression with large oval port heads and it makes nice midrange power. I'll eventually get the tbichips guy to burn me a chip, but it runs pretty well as-is.

[lofly'a]

thanks clay, what did you do to accomodate fuel delivery. any other special watchouts.