You can probably unscrew the studs out of the intake manifold a couple of threads, as long as you reinstall them with red Loc Tite. That will probably give you just enough extra stud length to use a gasket on both sides of the insulator. It might not be absolutely necessary, but it probably won't hurt, either. Just be sure not to block any vacuum passages with the gasket(s).
If you remove the studs, you can also draw-file the top of the manifold or use a disc sander on it to be sure it's flat before re-installing the studs or putting longer ones in.
Jerry
