Removing it is pretty easy. I've only helped do it with a friend's rifle once and it went smoothly. The pins that hold on the front sight/gas block are taper pins, so make sure you're driving them out in the right direction with your punch. There may be some curled up metal around the pins on the side they went in from, you'll want to drive them from the opposite side so they go out the same side they went in, otherwise you're just beating them in tighter.
Alignment when you put it back together can be a concern. First there's return-to-zero, they might not go back in the precise same spot but they should be in adjustment range. More important, like you probably already figured out, is the gas port alignment. If you're using the same parts and just changing the end cap, I think you should be OK. Just use a smaller punch to line up the holes when you're putting the taper pins back in, and it takes some pretty good pounding to get them back in. The HBI gas block aligner can help make sure you get it lined up.
Windham has a write-up at
https://www.windhamweaponry.com/hand-guard-cap/