I've got a 289 performer edelbrock with a 3/4 spacer that a holley 600 sits on. There is also a 3/8 " heat insulator that sits between spacer and and manifold. Is it necessary to run a heat instulator when using a spacer between the carb and manifold. I'm currently fixing and intake gasket leak and was wondering I need to put heat insulator on - current one is shot. Appreciate any feedback. thanks