Most of the switches I’ve come across if not all are simply two plastic parts mated with press fit pins and no glue and can be separated to either examine the internals or alter the leads. Justin showed us how in his example Modding a Judco switch . Without opening up the switch to solder the leads loose, wrapping it in a wet paper towel will help but the most important thing is get in and get out quick with the iron, don’t keep heating and fussing with it. Get extras, figure you’ll need them, and don’t sweat it if you screw up, just do it again until it’s right. If you do melt one then use it to practice on until you’re confident of gaining a good result. Much of successful soldering seems to come from having the confidence to proceed with alacrity.