1986 Camaro problems

So my car is a mint body 1986 with the
2.8. I know very little about cars and how
to fix them but I have learned a handful of
things and currently my car has died. Last
time this happened it was a fuel pump that
died and it was swiftly replaced with a
$400 repair charge but this time it seems to
have happened again and we don't rightly
know why since the pump has been
replaced twice in the last 8 months. Now
we know the wiring is weird in places like a
sub that's been placed in the back and
wires that completely seem to divert
everything around the brain of the car. We
have replaced the relay so we don't know
what or why it keeps burning the pump. I
haven't checked every inch of the ground
but I think maybe it time to cut dry and sell
if I can't find a solid answer.