The issue I see, using an isulator, is that it could possibly work against you, especially in a street driven car.
For example, Pauls manifold heats up under cruise when the airflow (through the manifold) is low for a long period. Its heating up mostly from exhaust (as you mentioned earlier, Pete) and to a lesser extent from contact with the head, and mabey a touch from reversion. This heat soaks the manifold, and in turn, heat soaks the IAT's mount. When he goes WOT, this "air cools" the manifold, in turn, cooling the IAT's mount. If you used an insulator (teflon tape, delrin, etc) then its an insulator both ways... drive for an hour on the freeway and the INSULATOR is going to heat soak... and it will take even longer to cool down at WOT.
In my opinion, there is no perfect place for an IAT. Just before the point of fuel contact would probably be ideal. Readily available sensors don't allow us to do that. So, every location is a compromise. The compromise that I choose to make is just upstream of the TB, mounted in some sort of plastic. Obviously, that won't work in your SC car.