sixt9x33rs: There are many. many different rust preventitive products on the market. I like the cosmoline product, it's heavy wax with a lot of solvent so it will spray. The military used it for long term armament storage. New black oxide bolts usually come coated with it. It is easy to remove with solvent.
I usually just spray it into a cup and coat the parts I want coated with a small brush. I would imagine you could put it over Boeshield, as always try an experment first.
'69 RS Z/28 Olympic Gold, 711
Flat hood no spoiler, black top, endura, 4:10
69 X77 Z/28 69 711 Original Paint Unrestored
'69 X66 Convertible Cortez Silver 712 black top Endura, auto, bumper guards, am/fm rear speaker 44k miles