Does anyone know the size fitting of the coolant temp sender for the guage. I put in auto meter guages and need to adapt the sender.Or where I can get an adapter.

The threads are NPT. You didn't say what year, so I'll guess it's 3/8". My local Checker Auto Parts carries a small selection of bushing adapters, and I"ve seen them at Home Depot before as well.

Best to take the housing off the car and bring it in to fit the adapter.