I tried a few different coatings with the really bad bits on my recent restoration.

The metal on my drop targets was screwed, lots of heavy rust in spots and zinc removed.  So I got them back to base metal and they obviously looked great but I knew they would rust again pretty quick.  On a cheapy pin it was just not worth the cost to get them rezinced or chromed etc.

So I had a go at spraying them with Silver Gal but it wasn't quite the colour I was looking for.  So I ended up spraying them a chrome silver colour then spraying a clear over the top to try and seal it.  The clear changed the colour of the paint under it slightly when it went on, it had almost a slight green tinge (I guess zinc or nickel sometimes looks like that too). 

It looked ok tho.  It's under the playfield so you obviously don't see it unless you lift it.  The end result looked better than had I left them bare metal and allowed the rust and white shit to come back.  It could chip off too despite the clear on top, but it shouldn't get too much damage now my resto is finished.  I will try and post some pics tonight of the finish.  Some of you guys will probably think it's sacrilegious but it was a cheap effective outcome and my other option was really doing nothing which long term was going to look worse.

I'm interested in the Autosol and WD40/fish oil idea to simply try and protect the base metal once polished and leave it at that.