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This jig will install the five trigger guard rivets. The front four rivets can be set at once and the rear will be done separately. There is a magnet that holds the rear rivet support to keep it from falling off.
The rear support block is removable to work with receiver flats that have the front four trigger guard holes in the wrong place as well as my flats and Nodak receivers that have the correct spacing. Removing the block also gives clearance when installing the rear rivet of the trigger guard that goes through the reinforcement plate.
The square block that sets the front rivets is made of heat treated steel and may need to be ground to fit receivers that have the bump on the right side rail.