Water Wash After Rust Treatment
The rust conversion product here is much the same as RustMort and the directions are to wipe or rinse with water. It tends to neutralize and cleanse the white powder that sometimes forms and that can bleed through the paint.
Once treated, the metal can often withstand a rain without having new rust form. That used to be on the label. I've had that but its best not to push your luck.
Degreasing should be done before the rust converter, and you should remove the loose rust before applying the converter. It probably also says to use several light applications instead of soaking it. The 24 hour wait is a very good idea. You need some but enough will remain in pits and the like to allow the oxide to form. Any bare metal will etch.
I'd choose finish paint as I said above - based on time available for primer to cure or omit the primer and use the finish DTM. If I had to work outside, I'd also decide whether to paint or not on temperature.
Painting under 50 degrees isn't a good idea and curing will take a long time. My 105 will either be blasted and shot indoors at a shop or it'll sit over winter if I have to do it by hand.
As for alkyd oxidizing faster - yeah, I believe it but how short of a time is 'faster'? Rust is virtually impossible to kill, persistant and I'll bet there will be reasons to fix and repaint far sooner than the finish of these modern products will fade.
Once again, it's all your choice in whether you want to be dunked or sprinkled.
