that wiring means having to use a 3 wire gm oil pressure switch
u can use a normal oil pressure switch and wire it to a change over relay
oil sender which ground when no oil pressure goes to pin 85
ign to pin 86
batt power in to pin 87a
fuel pump wire to pin 30
start signal to pin 87
pretty sure that's right
anyway I just use a modified rpm activated switch
or just get an lpg gas switch
only triggers fuel pump when u have rpm