As part of the coolant refurb I'm replacing the thermostat, so new one has arrived from Graham Goode, but its different from the one o took out, it has a rubber seal around the edge which in theory would make a good seal with housing lid..... question is, the gap in the photo is before I tighten the bolts so is this correct, or do I remove the outer seal off the new thermostat and just seal with gasket seal..... Apologies for all the questions, just want to do it right..
All advice is much appreciated....
New thermostat sat in housing.....

Picture of thermostat housing with thermostat fitted before bolts are tightened....
All advice is much appreciated....

New thermostat sat in housing.....

Picture of thermostat housing with thermostat fitted before bolts are tightened....

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