The size of the bolt could be around a 6mm thickness with around 60mm long maybe. Just make sure the length will work with whatever spacer that you use. Using a wing nut is great on the inside of the for a quick release if and when you need to put it flat on a table to work on it. Use a washer on the outside between the pack and the head of the bolt. The spacers can be 3d printed or grind down some hockey pucks for the spacers. Bishop and Canpara had done this and it looks great! Here is a link to the 1st page of one of their posts on this.
http://www.gbfans.com/forum/viewtopic.p ... ghts+build I should have done this but I have 3d printed spacers as of now and they are working as intended. I have a bucket of 30-50 pucks from playing hockey so I have the material to try it.
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