I've got a JCB 1550B. My swings were leaking. I pulled them both out. Was a MAJOR pain in the hiney. Had to remove the bottom plate without them both falling on my head. Got them fixed, putting them back was DOUBLE MAJOR pain in the hiney because now, I am trying to balance both of them along with the (approx) 1" steel plate that sandwiches them all the while, hoping the three parts don't fall and hit me on the noggin.
I got it done with a bunch of straps. After I was done, I smacked myself, I realized I could have removed the rods and left the cylinders intact. You won't have that luxury as best I know (maybe it can be welded in place?? I have no clue about that stuff)
May as well put new gaskets/seals in both of them, much easier to do it while both down than later on.
Here's some pictures of what I had to do. Also, take note of the connection hose that is mated to each of them, I don't know the name of it, but it allows them to move in tandom.
I took some pictures so I'd get all hoses back in correct place. I also used this opportunity to replace the nuts/bolts that hold the bottom plate on.