chevy starting

I have a 1987 Chevy 5.7 liter 350. Recently I changed the truck over from throttle body to carbuerator, took off all emissions and also switched to mechanical gauges. I put new intake,distributor,headers, and a fuel pressure regulator. I kept all the wiring that was not needed tied up just to make sure everything was going to work properly. The only wires that were left around was a brown wire going to my alternator and the pink wire that used to go to my coil for the positive on my new coil. Everything was perfect for a couple of months until I decided to get rid of all those wires. I started by taking the two wire harnesses out of the computer under the dash on the passenger side and another harness that was close by. I then passed the wires through the grommet on the firewall and moved them to the drivers side to go from there, in the process having to take off my distributor cap. I then went to start my truck only to find out that it would run for about 30 seconds and then die. I removed my computer and temperarily hooked the two harnesses back up plus the third harness that i had to send through the dash. Just to find out i have the same problem. My fuel pump does primer when i turn my key on. I've tried putting gas in my carb bowls but still the truck only runs speratically for about 15 to 30 seconds. Is my fuel pump not coming on after the prime? with no rpm or oil pressure being sent to the ecm? and why would it just now happen? because i disconnected my computer? I would appreciate any help I can get. Thank You