putting bearings in kind of ghettoly but works the best for the cost of the materials
3 in 5/16 bolt the same one for bolting foldys
slide one bearing on the bold, then the wheel, then the spacer, then the other bearing, then more spacers until they are higher up on the threads. then and optional washer and nut. tighten the nut and kind of guide the bearings so they go straight in. eventually the pressure will push in the bearings and you won't ruin them just make sure not to over tighten