Pontiac Repair: Thermostat question..., buick lesabre, david gardner

Question
Mr. Puccio,
I've got a 2001 Buick LeSabre, and need to install a new thermostat...but instead of a gasket, it's got plastic housing ring.  It's got a groove along the OUTSIDE, which seems strange.  Exactly what do I have to do in order to install it correctly?  Does the ring go underneath or on top of the thermostat?
Any suggestions or advice you can offer is GREATLY appreciated.
Warm regards,
David Gardner

Answer
Hi David:

get the correct Thermostat from the dealer. The aftermarket ones are fits all ones don't fit all! that engine gets a thermostat that has a rubber seal that is on the outter edge of the thermostat and that is what seals the thermostat to the intake manifold and also the water outlet neck to the thermostat. that application doesn't have a sperate seal or gasket it's all in one. good luck :)