Sierra 1500, fixed stalling then a code 54

My old 1500 has acted up intermittantly over the last year, stalling randomly, usually when coasting or stopping (see old thread on "stalling and stumbling.") On sage advice I recently changed the ignition control module at the distributor and it has stopped the stalling. I had also changed the fuel pump, strainer, filter, plugs, and fuel pressure relay before replacing the ICM. The truck ran great for about 2 days before beginning to run rough (but not stall) and yielding a code for the first time ever. The OBD-1 chart says 54 means "fuel pump relay low voltage." I am not sure if this means into or out of the relay. I cleaned up all the contacts anywhere close to the relay and wiring, but am not sure what to look at next. It seems to be getting progressively a little worse, though the symptoms don't seem to start for a minute or so after a cold start up. While the ICM did fix the stalling I had finally discovered that I had spark during the outages, but no fuel at the TBI's. One or more components (ICM only?) was evidently balking and causing the fuel flow to stop. I can't help but think that I have only partially fixed the original problem. Anything stand out to you guys, other than that I don't know what I'm doing over here?
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