mag thermostat housing?

Try google search for Cooling depot 85181. Thts the part # for the cast aluminum tall one that fits. Its probably under $15 your cost and will work well on a truck due to taller rad. If you cant find one, find me and I can help.

Thanks for the tip, does it have a 3/8 NPT thread for a gauge?
I did a google search and did not find it for some reason.

Edit, I found it 8.99
I can get aluminum bungs from McMaster Carr and attempt to tig it, depending on how good the casting is.