what i have learned in my schooling is that a missing wheel weight could not do that. it is slightly possible that you warped your flywheel or trans input shaft, in the accident, and that could be why the vibration goes away when you disengage the clutch. since your gears are brand new and were pro installed i wouldn't worry about that being the problem. it most likely is from the trans, clutch assembly or one of your t-cases. i hope that may help you.
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