So I've noticed, only at night; likely because it is too dim in the day time that the warning lights for my oil pressure, coolant and alternator will become illuminated brightly when I'm in a higher rpm, I don't necessarily have to be in high load. Battery receives 13.5v+ at idle, I have the low coolant sender grounded to disable the buzzer, oil pressure sensor does work properly. Oil pressure reads around 50-60 psi during cruising and I notice the two warning dots and alternator light become illuminated.

Vehicle mods that might matter are:
(USDM MY1994)
Single turbo w/v-mount
AEM Series 1 EMS
UR Style under drive pullies
Relocated battery, 0 gauge welding cable.

The car has a decent amount more of mods but I can't think of any others that might matter.