Any aftermarket alum. intake SHOULD theoretically bolt up to you stock exhaust, but in reality, many WON'T. The heat riser flange angle won't be right to match up to the exhaust and will need to be milled. If too much material is already gone, a thin spacer will need to be made to take up the gap.
The idea is to get the intake and exhaust manifolds bolted together tight (with a gasket in between), and still have the (3) alignment rings on the intake ports line up and the studs on the ends of the ends of the exhaust manifold line up. Easier said than done sometimes.
