91 Ciera Thermostat
 

Okay, so this is what has happened thus far. We got the housing off, and the thermostat out, but when replacing it, we got a bit confused on whether the gasket goes on the engine or on the housing (It has been a week since we pulled off the thermostat housing, but the daylight faded lol). I would really appreciate some feedback if that is possible.

I have always put the gasket on the engine side, but if it leaks, swap it. Some thermostats don't even need a gasket, so it might not even matter.

This one does need a gasket unfortunately...thank you for the advice though. I will try it, thanks again.