I recently purchased a pair of the Progressive 418 rear shocks. They are 12.5" eye center to eye center. I test fitted them with the stock wheels and tires and would have to modify the side and center stands. I also have a Kosman 18" rear wheel with a 170/60/18 tire I want to mount. Has anyone tried this combo? (12.5" shocks and 18" wheel). I don't want any tire / fender clearance and/or cornering problems. Any idea how much I would have to lower the forks in the triple tree to compensate? (Also have Race-Tech springs and emulators installed without the lowering kit). Info and comments appreciated!!!