sandy- cole hersee #75600-4 12vdc.
i got it thru a local auto parts, but i expect marine supply would also work.
note that the switch part is a 2" cube, so don't do what i did, and make sure you have the room(i bored the hole first).
thanks for the radiator comment.
i still have the original radiator, but i think it needs recoring. this mr2 radiator fit where the spare would no longer fit ('cause i like the waterpump),and was much more efficient.
i considered a cutout in the left well, but added some foam air dams to force most of the air thru the radiator, figuring it would have to use the existing opening. so far good enough, but i may revisit.