Fuel Pump Primary Circuit Failure Error 556 HELP!!!

I have a 91 F150, 302cid, 4x4 and dual tanks. It quit running on me and the error code I am getting now on the KOEO is 556 Fuel Pump primary circuit failure. The odd thing is I can hear the fuel pumps (either one, doesn't matter whichb tank I'm on) prime the system when you first turn the key on. I don't have a pressure gauge so I didn't check for proper pressure. It is not even trying to catch. Just turns over like crazy. I have replaced:\
ICM-distributor mounted
Magnetic Pickup -inside distributor
EEC Relay- checked bad but made no improvements
I am ready to go get a new computer but figured I'd check with you guys to see if anybody has had this problem
Please Help---considering Molotov Cocktail Theory

You should have three pumps, one in eash tank, plus the "main" pump on the left inner frame below the driver's seat. Check the MAIN pump for working, as it will not run on just the in-tank pumps.

According to the manual and what I have seen on my truck. There is no 3rd pump. only the FDM as they call them in each tank. The pressure regulator is up on the fuel rail. I am at a loss as to what else to look at. It is driving me nuts!