This trigger is not for current production Gold Cups with the standard-width trigger shoe. This trigger works with the original National Match Gold Cup 1911s with the wide trigger shoe. The trigger shoe measures .340" wide to fit the extra wide trigger shoe slot on the original Gold Cup frames.
The original Gold Cup trigger was all-steel and while very cool looking with it's cresent-shaped cut in the shoe, it was a heavy beast! Because of the great mass, Colt engineers had to add extra parts to the sear to help dampen the effects of trigger bounce, which happened every time you would release the slide by the slide stop. Usually, the first time the pistol was taken apart for detail cleaning, the tiny spring and the sheet metal link were left behind if not lost outright because they were fairly difficult to reassemble. The steel triggers were also typically pretty loose in the shoe to frame fit having a lot of up & down play. Another problem with the original GC trigger was the over travel adjustment could readily turn under vibration, changing the overtravel adjustment.
The better solution to this is a lightweight trigger with extra material left in the height of thte trigger shoe so it can be fit to the frame. This relieves the trigger bounce problem with any sort of reasonable pull weight and gives you a consistent feel having eliminated the up & down slop. The final improvement is the fixed over travel stop that cannot come out of adjustment. It is a small section of the trigger shoe that projects rearward just below the trigger bow. Same place as the screw used to live.
To adjust over travel, you have to file the fitting pad to set over travel. Once you have the trigger fitted to the frame so it will go all the way forward and move back & forth freely, you have to assemble the fire control group in the frame. Then test to see if the hammer can be lowered (controlled by your thumb) when the trigger is pulled to the rear. If the sear nose will not come out of engagement with the full cock notch, or the sear nose is "bumped" by the hammer as it is lowered past the half cock notch, material needs to be removed from the fitting pad. Repeat as needed until the hammer can be lowered without feeling any kind of bump or rubbing from the half cock notch. Then check to see that you have full captive engagement when you cock the hammer to half cock and try to pull the trigger (not applicable to Serie's 80 hammers w/o captive half-cock notches.