Chevy began putting Rollers in engines in 1987. If the engine is a 94 it has rollers. You can't use the LT1 aluminum heads with an intake manifold. It takes more than just gaskets. They work with Fuel injection only. I am not sure if you can buy an aftermarket manifold that is made for the LT1 heads or not, never checked in to it. You can install the fuel injection system from a LT1 but the intake has to be drilled to accept the distributor.
Ed