The 200 I've swapped into my 63 Falcon van is out of a '78 Fairmont, and the temp sender on that engine is 3/8 or 1/2 inch NPT (I think?). The sensor I bought for the '63 170 from C&G looks like it's 1/8" NPT, but isn't. I was going to run the 170 sensor, but it's too small to fit in a 1/8" brass bushing to adapt it to the 200.

To my question: I was going to purchase a sender for the Fairmont (same as what came with the engine) but it's not available for a gauge, only a light. But the sender for a Granada the same year is available for a light OR gauge. Do you all think it'll work?
Or is there another option that will allow me to use the stock gauge in the van?

 

they vari by ohms, The one you have from the 63 IS 1/8 pipe thread. If it doesn't fit your adapter you need to get another adapter or a new '63 sender if the threads are bunged up in your sender.

 

An update, of sorts.
The van is running (burns a LOT of oil, but it runs), and I used a Grenada sender from NAPA - TS6153. It screwed right in to the block, and moves the gauge like it's supposed to. There are no temp graduations on the gauge, so it will operate fine.
The Sender from C&G Ford was a dud - too small for the 1/8" hole in the back of the 170 head. C&G offered to refund my $, but the postage was nearly as much as the gauge. I'll just avoid C&G from now on.