Using a scrap of 1018 steel I now have small (1/4"x20 bolt) side clamps to hold the material on the label jig. Have to remake one of them. Threads for the clamping set screw broke into the clamp-down screw hole.

Side-clamps for 1/4"-20 blots.

Side-clamp showing error

Also made T-Nuts for the 1/4"20 bolts that fit in the jig T-slots.

1/4"-20 T-bolts

1/4" T-nuts with T-slot in jig