In short, yes. I do this often for engines ranging from Model A's to Studebaker flathead 6's to even aluminum marine exhaust manifolds. The cast intake and exhaust manifolds become distorted from all the heating and cooling cycles over the years and no longer form a single flat surface when bolted together. Disassemble them if you can, clean all the rust and crud off them, bolt them back together as best you can, and then have the gasket surface milled as a unit. Will be perfect then. Some shops also use what amounts to a large beltsander to surface these. Either way. Try NAPA in Northfield there, they do alot of tractor work and should be able to help.
