Fuel Pump Relay noise

[GremlinMKIII]

car specs

1987 Supra 7M-GE

bought the car a while back with 350k km on it (body has a bit of rust, but all in all not so bad) it had a blown up engine the guy had already swapped out for an imported engine with 64k km on it but he never got it running.

the guy didn't connect everything back up properly when he had done the swap himself so myself, my brother and my dad did a rebuild of the new engine and put it back in and hooked it back up (to our knowledge, it's hooked up just fine) but the engine will not start!

first we determined the engine wasn't getting gas, so we took the gas tank out and discovered the fuel pump was in pretty crappy condition, so we replaced that right away and now the engine is indeed getting fuel, but again won't start.

since the day I got it though, it has had a problem with the fuel pump relay making a buzzing noise as soon as you plug in the battery terminals - entire car gets power, everything inside works, but engine won't start (tries to, but just keeps turning with no actual start)

I have scoured the internet for a couple months now trying to figure out a solution to this (haven't been in a big rush due to having my license taken away for medical reasons, but I just got my license back yesterday!! I need my car to start now!) Haven't had any luck finding a solution to this problem - lots of other people having the same problem, but nobody posting a solution.

does ANYONE know what could be goin on???

thanks.

(yes long post, I know..)