Bob, the ripple location is across a part of the inner panel but does not correspond to the shape of it. Half of the ripple is in an open area and the other half is in a closed section, sorta' like the edge of the inner panel and the ripple direction forming an "X" (hope that makes sense). I checked material thickness with an old Spot Rot gauge and it pulled strong all around where the ripple appears, so I assume very little build in that area. It did indicate some filler material about 6 inches to one side but it also had a good pull as if it was slight build.
I will try the heat/cool cycles. It is forecast to rain tomorrow and be in the 50's for a while so good sun is not available soon. Can I use an Infratech medium wave heat lamp? It can easily get a panel hot quickly, as you well know, but it will not be an even heat across the whole trunk lid. Thanks for the tip!!
It looks so good while in the shop and most likely my customer would never see the ripple outside (when it heats up) as it will be white and he is not extremely picky. It will be mentally and financially painful to strip it down but I will if I have to. Thanks for your reply.