Believe this was posted a while back by 260RemGuy:
"Enclosed in box with Redfield RE-24 receiver sight is a "riser block" 0.210" high, 1 12/32" long. Remove factory front sight, and place "riser block" on barrel lining up hole in block with hole in barrel, place factory front on top of "riser block" and attach with screw furnished (screw 9/16" long, 3-48 thread)."
Also, Lyman offered a high front replacement sight for the "rimfire" 24's. Their model 22 repl sight sat in the footprint of the factory sight and used the factory screw. These are commonly found behind the ears of most unicorns. This sight was likely offered byLyman to pair up with their 53D side mounted peep.
