Hi gang, long time listener first time caller. My thermostat housing has a slow leak where it connects to the lower intake manifold, which is corroded and needs replacing. I have the manifold on order but I need to know before I start taking things apart - is there a gasket or O-ring between the thermostat housing and manifold that needs to be replaced, and if so what is it? My default assumption is yes, but I can’t find a diagram that specifically shows the connection or a good picture online, and I’m *not* draining the coolant to take it all apart until I’m good and ready to start. Help!

Picture attached for clarity.