The op switch like I said goes directly in the block and there are only 2 and they all have the same thread size.Make sure someone didnt screw an adapter for a mechanical gauge in the hole.The temp sender if you changed housimgs that might be the problem.What connector does your harness have?A lot of the housings have a hole for the sender and a plug that is a different size on the other side.That way either sender fits.Rocky