thin metal works best,I rvt it to the head,then install the gasket and intake
if its 2 thick it will/could cause an intake leak or suck oil into the port..DAMHIK
another way
I use the permotex copper and fill the heat cross over in the heads,about 2" deep,then smooth off at intake surface,let cure over night
never seen that stuff move or burn yet
been sealing old header gaskets for awhile with it also
it does not get any hotter than right there at the bowl behind the valve and the top side of the exhast port into the header flange
if it dont burn there after 2yrs,its not gonna burn
if that is not to shadetree for ya
that crap plugs up the flow of a radiator pretty good also