I had a Stewart Warner temp mechanical temperature gauge but I didn't have an adapter. The local auto parts store wanted $10 for the adapter OR you could buy a whole new modern temperature gauge for $20 that comes with the different fittings you need to install it. So I got a new snazzy one for the time being. I will replace it with an Autometer gauge in the near future as they are a higher quality product and I don't mind spending a few more dollars to get a better product and match my current array of gauges. But for now the twenty dolla special is just great.
And here we are with the proper fitting installed which will give the sensor a solid seat to be placed in. Now to install it in the truck.