From looking at the manual, it does seem straightforward-but I know how these simple things can go. I'll try it without removing the whole arm first & see how that goes. I'll report back & let you know if that works.
I went into my local AutoZone looking for wiper refills for my Prius. The clerk told me they wouldn't last a month, but the wiper blades? Well, that was another story. So he brought me to the blade section. He even offered to put them on for me.
By the way, they (Anco) ain't cheap.