Having trouble finding information regarding the size of the bolts for rear wheel weights (Diameter Specifically) any help would sure be appreciated.

5/8 11 but length depends upon the style of pie weights that you have.

Best bet is to mount the disc and buy a couple lengths to experiment. If you use bolts that are too long you can crack the mounting disc if the bolts bottom out against the wheel center.

I sold the pie weight kit for my '52 8N several years ago, so I am going from memory here, but I am fairly sure the bolts that attach the pie segments were 5/8-11 UNC and 1½–2 inches in length. If someone else doesn't chime in with info on this, hit your local hardware or big box store and buy one of each length and try it.

5/8-11 x 3

Thanks, Rob!!