[/QUOTE]What ever the thread in the manifold is, 1/2 NPT more likely than 3/4 NPT, you will have to bush it down to the sender thread if not a match. 1/2 NPT is common for temp senders, and BBC manifold heater and by pass hose conections...MP[/QUOTE]
Right you are... 1/2 not 3/4.. DUH!