So, I found a G42 follower but it was rev 2 and my gun is rev 3. Created this in Tinkercad through 8 iterations. This one works really well. Be sure and sand the top surface nice and smooth otherwise you may have issues getting the last round properly loaded. This follower will turn a standard 6-round mag into a 7-round mag without adding an extension. ;)
G42_7-round_Follower_Mod8.stl | 76.6KB |