Thermostat question

I have a dumb thermostat question. When installing a new thermostat do you put the thermostat in first, then the gasket, then the housing or is it gasket first then the thermostat?

Thanks
The first thing you should do to a new thermo is check it in a pot of boiling water to see if it opens as soon as you drop it in. Then install as directed if it's good.
My $.02, Good Luck!