Temp gauge spiked

Not really (Tests involving "not removing). The wire goes from the sender, through the bulkhead connector to the cluster. One wire. There is a chance it could be shorted somewhere, examine the harness running along the engine. Otherwise it's pull cluster time

Do you have a factory oil gauge? Did either that or fuel also spike? That would indicate problems in the IVR. I've forgetten "I think" the IVR in yours is inside the fuel gauge. Will have three stud terminals.