I ran into the exact same problem with the collar on the thread and saw your post. I called Benelli, received and installed the correct RCL SPRING ASSY and the steady grip. This helped, but did not fully close the gap between the stock and receiver. I went through all the accessories including the shims that can be put between the stock and receiver to fill the gap and they are not compatible with the 2 male prongs sticking out of the stready grip stock that just barely "plug" into the 2 holes in the receiver. Any advise?