There are a number of immersible products available that might preclude the disassembly of the latch.  Many are phosphoric acid based. Alternatively there is an electrical process using water, washing soda (sodium carbonate) a batter charger and a sacrificial piece of steel.  It is truly amazing to go back a few days later and see the rust transferred from the part to a piece of scrape steel.  Look it up there are articles all over the internet.  The first time I tried the process was on a very rusty file. Wire brushing it did little to get the rust out of the crevices and ran the risk of removing the sharp edges. The electrical process cleaned everything and retained the sharp edges. The image is of the file and transferred rust to a piece of angle iron. Obviously lubrication should be applied afterwards.

Disassembly would probably not profit much. The removal of the rivets can potential damage the housing and those are not generic pop rivets holding the piece together.

I'd think you would need an internal spacer (maybe a stack of washers) if you used a bolt and nut so you didn't crush the halves when they were tightened.

If you really want to take one apart, I'd suggest getting a spare one to practice on just in case you find out you can't get it back together.
I'd go with the idea of soaking it in something as mentioned above. Granted you wouldn't really be able to paint/protect the inner workings afterwards, but probably the safest way to go. They didn't come painted on the inside anyway, so as long as you keep it lubed it should be good to go.
Russ

Local rad shop acid dipped a part for me, then I cleaned & POR 15 coated.

But with your part, it would need an anodized (?) type dip.
I'd have to google how to....

(zinc plating ?)