Ed,

 

I’m happy to say that your Earls part number will work fine.  I may have to elongate the holes just a tiny bit, but it’s as close to a perfect bolt-on as you’re going to find.  Thanks again. 

 

For the sake of the archives (if there are any), here’s the full lineup of Earl’s thermostat housings for the common 2^nd Gen water pump housing.  These have room for a thermostat, and have an AN16 fitting on top.  Total height is 2-1/16”.

 

Earl’s #

166006 – Anodized Silver

166106 – Anodized Red

166206 – Anodized Blue

 

Rusty