Just drill a few holes in the weight and bolt it to the underside of the wheel., assuming it will fit inside the barrel area and still allow the bead area to sit flat on the floor.
Jerry
Cutting a square hole in the middle and sliding the 50# weight over the post was PLAN A but was too much effort. Your suggestion was PLAN B and the one I used. See photos in the link.
VISE Fabrication plus VIDEONotice in the video how I lose MY BALANCE but the VISE STAND is rock solid. I was NOT DRINKING, and NO . . . . . I will NOT show you my TIG welds. Not very proud of them. Gotta keep practicing.
Jay