gauge swap issues

so I swapped out my idiot lights for a full gauge cluster and replaced the sending units and now neither of the gauges work, the oil pressure being i dont have the wires for it or they've been snipped. but i have all of the wires for my coolant temp gauge and it doesn't work either. any tips or tricks?
btw its on an 88 model

So I got my sensors all hooked up and my oil pressure is reading about 7-10 and my coolant won't go above 100

Dunno where you got yours, but parts store sending units are bad more often then good, right out of the box.

VERIFY they are bad with a laser thermometer and mechanical oil pressure gauge, after that, good luck finding one that works correctly... I upgraded to proper gauges.

I tested the coolant sensor with a multimeter and a lighter seemed to work and a gauge worked for the oil pressure but i only sometimes get a reading on my oil pressure, any grounds or plugs i should try cleaning?

Its a long shot, but i recently fixed an intermittant fuel level gauge by taking the dash apart and playing with the plugs on the backside of the instrument panel.

Old school gauges use a little coil on a 5V circuit with a variable resistor (sender) on the ground leg. Power to the coil produces a magnetic field that tugs the needle. Resistance on ground leg makes current drop, producing smaller field.

Simple way to test these one-wire senders is to just disconnect (ground leg open, infinite resistance) and see if the gauge falls to bottom, then use a piece of jumper wire to connect straight to ground (no resistance) and see if the gauge pegs to top. If it doesn't do that then there's a problem with the gauge and/or wiring, if it does work then the problem is with the sender.