Little more updates. I abandoned the steel magazine project and figured I would try an aluminum.
Machined a small mag well cover that I tapped and bolted a magwell to. I made the well out of the same little chunk of aluminum. I guessed and made the shape of a follower that I thought will work. Finally made a few springs out of banding and tempered them in the lead pot. They worked out okay I suppose. So here's the next pieces of the puzzle...still waiting on a die from Whitten.
The mag well cover is held in by the action of bolting it to the mag well and a small 4x48 grub screw for rear tension.