The rear mounting hole of the tank is a pretty big hole and to find a bolt to go through it and the frame, I'd have to drill a hole like 5/8" through my frame. I wasn't doing that. I found a sleeve to resize the hole, but it wouldn't allow the tank to come off the frame if need be, so I had to look for an alternate solution. As it turns out an axle from an old bike wheel and the bearing collar would center the tank hole on the frame. I cut the axle off at the correct length, good end, and welded it to the frame. Couldn't ask for a better result. Bonus pic! The forward tank mount.