something to think about. like I said, I went to troubleshoot one in an 87 the other day.
The connector at the fuel pump on mine was all nasty in the ground area, tons o resistance. I bypassed the connector and wired the ground straight wire to wire. That and a little knock on the tank with a 2x4 while providing 12V to the pump fixed it. Mine needed a knock because it had been sitting for a while, but the ground at the tank (tab on the fuel sending unit) and the ground at the plug were my culprit. I'd really look at the sending unit side because that tab is exposed, and in an area that catches a lot of road grime.
at this point I would probably hot wire the pump to 12V and ground at the socket to see if the pump is working. I use speaker wire, because it's got two conductors handily right together. Obviously this is only for troubleshooting in the driveway.
If the pump works hotwired to the battery for 12V and ground take away the hotwired ground and see what happens. If the pump dies wired straight to the 12V but using the factory ground then you've got a ground issue. If not, then you've got a 12V to the pump issue. If you get nothing with the hotwired pump you have a problem with the wiring in/at the fuel sender (you did check that ground tab right?) or a bad pump. If the ground tab is shot, or torn of as it was in my case, you can drill a small hole to the 10 o clock of the fuel output, and use a self tapping sheetmetal screw and a ring terminal to get a good ground bad. Cleanthe face of the sender before you drill the hole. I did this still instaled in the tank and didn't blow myself up, but take it out to be cautious