600 cfm on 460?
..... JB Weld is an epoxy metalic compound commonly found in a tube like hobby cement. Although "JB" can be very convenient to use and helpful in some applications, I do not recommend use of this product on an intake manifold to plug EGR holes. Since there is no way to determine end user expertise the application could lead to disasterous results.
Fel-Pro brand gaskets are good quality gaskets and yes, pricey when purchased one at a time as opposed to a subset. Any good quality gasket used along with a thin metallic base such as brass shim stock will contain the exhaust gases as indicated above when applied to a flat clean surface.
Merely place the blank (brass/copper/stainless gasket) before the new gasket, then assemble. Using this suggested method, you can always return to stock if you change your mind, or later want to sell the intake at a swap meet or on eBay.




