I used glossy white Lustrekote on my T34B and now the white on all of the control surfaces is changing to a rust color. Of course, I will never use LustreKote again. I am considering putting white ULTRAcote over the entire plane. What should I do to prepare the surface before applying Ultracote? Sand with light sand paper, remove every last speck of dust, then cover? Should I use something more aggressive to prepare the surface? But I gotta be careful because I don't want to put something on there that will turn the old Lustrekote to goo.

Thanks
-oliveDrab