Don yes on the thermal paste,
If I use a clamping strap to hold it in place,
There is and industrial epoxy that is used to hold heating elements (like those used in rv fridge, in some types of Mfg machinery, it sets
Up cold, no heat, ivory white in color, and transfers heat from heating element to metal it's mounted in, but I don't have any and I don't remember the product name,
Replacing the burned out heating elements in machines used to plastic weld the ends on some plastic fuel cell canisters, the company was mfg the empty canisters, that were shipped out to be labeled and filled
Any way, this is just background info that products exist have bonding ability and heat transfer, and not be a thermal transfer barrier