Folks - I am replacing some very old/damaged D/H windows with vinyl replacements. Have done so successfully in the past many times, but the sills were level. In this case, the sills are sloped to the outside, on the order of 1"/12". What is the best way to deal with this? My thoughts were to be to cover the sill area with coil stock extended to meet over the exterior coil stock trim, and caulk the seams and window base. Is there a better way to deal with this? Does this area need to be shimmed?