The design is all done, but hasn't been cut. The bungs would weld into the runners. The intake would be cut with 1.6" diameter ports, and that's with extra material for enlarging. Material could be either steel or aluminum, depending on if you have TIG or MIG access.
I will not be making a large run of these pieces, like I did with the exhaust flanges. There is simply not enough interest. HOWEVER, we can do single flanges for those of you that want them.