Not sure if it would stand up to welding - the metal is very thin. However, the metal part of the switch lever goes all the way up inside the plastic cap so you should be able to slide it up out of the way...

I reckon it'll be OK. Don't cut the switch lever unless you're sure you have to - you might already have enough metal to work with, you'll just need to find a way to hold the tip of the switch in place. The tip just slides off, which is why you see so many people with them missing....

That's an option too - just leave it off... the switch will still work fine...