OK so I did this today and yes it was a PITA, and no way am I ever putting them back on. To me the zippers were the easiest part, I mean everybody knows how a zipper works you just gotta find the other end tucked inside the fabric. Took me a while to figure out how the fabric clips at the base of the seat came apart. I found that a putty knife was the perfect tool to both undo and redo the clips. I was never able to pull either the fabric or the foam off so instead I reached up inside with a small socket wrench and undid the bolts completely by feel. That was easy once I found them. By the way the bolt heads are in the front of the seat (not the back) and between the metal and the foam. The worst part was dragging the whole headrest assembly out of there through the foam. It kept wanting to get hung up. Basically you have to reach up in there and lift it up and then forward to clear the bracket and then wiggle it down an inch at a time. I didn't disconnect the cable until I had the assembly hanging out, oh and I unclipped it from the assembly end and left the cable inside the seat.
I have a 2015 JKUR by the way and my seats are full leather. There was a horizontal seam in the front center where the leather was fastened to the foam and it prevented me from removing the leather. If you can get your fabric off it will be a lot easier.
After having did it I have no regrets. The leather still looks great. I was worried it might look a little stretched out or wrinkled after man-handling it but you can't even tell, except that the headrests are gone bye-bye.