I derusted a vise left by the previous tenant of the house
I had no free buckets to hold the derusting solution in that the vise would fit comfortably, so I had to use a plastic box that was too wide. It would not submerge fully in the 1 Liter of derusting solution I bought, I had to soak one side for 24 hours and then the other side for 24 hours. It mostly cleared the rust. I'm considering painting it now, but I don't think I'm going to.
I did in the end end up painting it a nice blue colour with a rust protect metallic paint. First layer looked awful, second layer looked quite nice already, but I'm gonna add a third one today. The paint can recommended 3 layers for proper rust proof, so that's what I'm going by.
For future reference, Eastwood make a rust removal gel that you can paint onto surfaces and does a pretty great job. There's also naval jelly which is a generic phosphoric acid solution that can also be painted on and washed off.
You might find naval jelly at a marine supply store, I think Permatex makes a version. The Eastwood stuff might have to be purchased at an commercial auto paint store.
You should definitely paint all the surfaces that aren't machined, as that's very likely how it would have been originally.
Also, what's dull about restoring a tool? There are entire YouTube channels devoted to it that are pretty darn popular. (Or so I'm told, as I would surely not watch something so dull myself. <AwkwardLookMonkeyPuppet.jpg>)
I am sincerely apologetic of posting content that you found not to be dull enough. I will try to be better in the future. Tool restoration indeed is interesting, but I thought merely soaking a tool in deruster for days would be dull enough :(