I have a liberty with 210,000 miles and original upper and lower control arms. Both are shot. Upper is badly rusted. Ordered Moog problem solvers for lower and a MEVOTECH CMS25156 for upper. No lift on vehicle and no off roading. I have seen on this site that some recommend filling the holes in the lower control arm bushings with windshield urethane. Would this be good to do on the upper control arm bushings to extend the life?