ok ive got a 350 4 bolt main block im building to put in my 83 firebird and i purchased a tpi setup for it the other day witch included "heads, injectors, fuel rails, intake, plenium, runners, throttle body, and ditribuitor" i know i still need a wiring harness and comp. what else will i need how hard will it be to install any and all coments will help thank you

Might want to look at a wiring diagram for the computer you plan to run and make sure you have all the sensors.

Since you don't have a computer yet, i'd recommend running the 730 speed density computer used in the 90-92 cars. Several reason.
-Very common. It isn't just an f-body ECM, it was used in a lot of appliuations like corsicas and berettas. So it's relatively easy to find and low cost.
-no expensive MAF sensor to worry about going bad on you
-overall it's a smarter computer. Also, tuninjg a 730 is a lot more well understood and 'easier' than a MAF car.

At the bottom of http://www.diy-efi.org/gmecm/ecm_info/1227730/ are links to wiring diagrams to get an idea of what you'd need. Alas, i am too tired to really offer much more detailed help right now, but a search on '730 swap' or other phrases like that should give you a lot of great info.

what about the fuel pump what do i need to do their also i was wondering about the distributor i have a new hei with a accel super coil is this compatible with the tpi setup or will i need another also i been hearing about a speed sensor that i have to have to make the comp work right whats the story about this? thanks