I would have much rather used mandrel bent pipe and built a complete new manifold as thief suggested. The only problem is I have no source for such bends. I looked into extrude honing but that was gonna run close to 500$ based on the pricing on thier web page I think Im in for about 25$ in sanding wheels and a new sawzall blade. I dont know if any one has paid attention but in stock form the upper intake has significantly smaller runners than the lower does. In hopes to maintain diameter Im using a 1.375" dia freeze plug welded to a long piece of flexable steel for a guide. Once I get the plug to clear 100% of the runner length I simply put the sander on and clean up everything. I know its not rocket science but Im hoping it leads me in the right direction. I have only 1 of the 90's left to port then its on to the straight sections and those should go fast.