I fixed my hammer follow and mag change problems.
I deepened the area of the stock that the rear of the trigger group fits into. At first I used a chisel, but found it difficult to work with the synthetic, so I switched to my dremmel. This made it easier to remove the smallest amount possible. I made the indentation about 1/16" deeper. I also extended this area rearward the same distance.
The trigger guard now slides into place with finger pressure. The trigger guard closes with a firm push. Best of all are that my hammer follow issue is gone and my mags are much easier to change.
The clue that tipped me off was a mark I saw inside the stock, directly above the trigger. The middle, deeper part there had a little indentation from the trigger contacting it. If you remove your trigger group and wiggle the trigger a little, you will see the little "horn" on top of the trigger. That is what was hitting the stock.