The wiper arm just pulls off. The wiper arm has female splines. The wiper motor arms have male splines. Gently pull the arm straight off and it should slide off without to much trouble.
If they will not budge, a small pry bar can help persuade them off. I would use a rag between the pry bar and the plastic nut that sits against the windshield body in an effort to prevent it from cracking while prying against it.
After having my ride apart for a couple months I wasn’t paying much attention when it came time to the re-install of my freshly painted wiper arms and I didn’t put them on the 45 degree angle, I just kinda laid them flat. I didn’t even notice til I’d been driving around for about a week and saw a fellow YJer driving towards me and he flipped me a wave.
Not only were they laying flat, they were backwards. If we’d had any rain and I’d switched them in, instead of swiping up they’d have crushed down into the cowl and done god knows what kind of damage.
But lucky for me, as added insurance, I’m enough of an idiot that I’d also forgotten to plug the wiper motor harness back in so it wouldn’t have been an issue.