After doing a fair amount of research I believe I found the issue.
Nodak Spud used to make a NDS-3 economy receiver which was supplied to Century for the GP 1975 builds. It was apparently made to specifically fit the Romy G kits. The NDS-3 had a long trigger cut which was reported to have issues using the Tapco G2 trigger group. Hammer follow and double taps were reported. The new receivers on the GP 1975's are Century made and still have the long trigger cut so they must be fashioned after the Nodak receivers. Tapco themselves recommend not using their trigger in these receivers.
So, I went in to my collection of spare parts and took out an old trigger group I had laying around and installed it in the GP. The over travel was reduced and the trigger is no longer hitting the rear of the receiver.
I don't foresee any issues now but will see when I hit the range. If I do have problems I may look in to the double hook trigger as mentioned and cut a more shallow slot on the other side to prevent the over travel.