[Lippyp]

Over here in the UK we know a bit about rust and how to stop it. In cavities I use an anti-rust wax called Dynax 50, comes in a big aerosol (rattle can) with a long prope with a 360 degree spray head, you find a convenient access hole or drill one if neccesary and insert the probe and give it a good dousing in wax, it creeps into panel joints and is self repairing so if it gets scratched it heals itself. It'll happily go over paint or bare metal and will keep the tinworms at bay for years. There are a fair few different brands of cavity wax available. Waxoyl is the biggest, Dinitrol, Dynax are others. When I replaced the rocker and inner it got a good spray afterwards.