I went to replace the thermostat and there is a big rubber gasket that sits on the mating faces. There isn't any recesses that fits down into. I placed the new thermostat on the face and started tighten the bolts and the rubber part on the thermostat squeezed out one side on the housing. ???????????? Does this stuff just happen to me? Any comments?

 

I had to make a paper gasket and remove the rubber one to make it work.

 

That is what I was thinking. But why the big rubber gasket? We may never know......

Thanks Nick.