Like the title says, I am putting a coolant sensor on the manifold. It looks like the threaded hole is 1/2 inch. The sensor I bought is 1/4 inch.

Do they sell 1/2 inch sensors or do I need some type of adapter to bring it down to 1/4 inch?

If they do sell 1/2 inch sensors, what do I tell the guys at the auto parts store when they can only find parts by make and model (since this is a new crate engine in a Fiero)?

Thanks for any help-