De-rusting while winter rolls on

Single digit temps outside make work on the truck kinda hard right now.  So, in an attempt to at least feel like I'm doing something, I am running a little test to see if I can salvage my park light housings or if I need to buy whole assemblies.  Since I'm doing everything on a shoestring budget, I would really like to be able to save the housings and only buy the new internals and bezel.  The glass was fine and cleaned up easily.  The outer bezel was toast, though, and will definitely need to be replaced. I'm also thinking about buying the LED insert instead of using the standard bulb.

It took a little persuading to get the nuts started on the housing.  At least I thought they were starting....  One of them sheared off and one of the came off.  So, if the de-rusting works, I'll have to replace one of the studs, at a minimum.  Here's a couple of shots of the housing from different angles:

Well, a couple of pictures tell the story.  You can clearly see that the inside of the housing is in pretty good shape.  The lens and gasket did what they were supposed to do and kept out the moisture. The backside and bottom were another story.  The last pic shows the broken stud.  I think that I can drill it out and replace it with a bolt of the same diameter.

To do the de-rusting, I'm using Evap-O-Rust.  I've used it in the past, with good success.  This housing is pretty rusty, so I'm going to be putting it to the test.  The tub that I'm soaking it in is not quite deep enough to cover the whole housing.  So this will be a 2 part effort.  I'll post an update when I get it done, likely next weekend.