If it is a 5 TERMINAL relay, it looks like the red wire is on terminal 87A instead of 87.

Do a wiggle test. Ive never seen a nelson harness, but i have had some terrible experiences with relay "harness" where the wire comes unsolderd from the harness female connector to the relay. What a paiiiin.

Relay's aren't that expensive. You could get one for 5 bux and swap it out and find out if the other one was non-functional. Replace it and connect it to gray wire on chassis and your fuel pump may work fine.