Cylinder Seal Replacement (530 CK backhoe)

1- What's involved in replacing the seals? Do I need to remove the whole cylinder, or just the shaft end (ie: can I replace the seals by pulling the whole thing out at the shaft end, or do I need to open the closed end as well?).

2- Is it usually just the shaft seal that needs to be replaced or do I have to replace all packings? (none realy drift when running, except the boom does drift very slowly down when running over time).

3- I was given a link to EPM.COM for seal kits for these tractor cylinders which was great since it lists by model and seal kit part number. However, for each actuator (say BOOM), it lists several part number sets, of which only one I can see in my parts number manual. I'm not sure what the others are for? They're likely the other seal kits/packings in the cylinder but I have no way of knowing. Anyone else use them or have experience ordering from them? Any other sites for seal kits?

I honestly have never done this on my 530 CK (I have only done this with smaller "ag" type hydraulic cylinders)- but the pevious owner did and judging by the burn marks on the end of teh cylinders, I'd say that they used a torchh to heat up the end of teh cylinders so they could unscrew them. Someone said that this job is a lot easier if you leave the sealed end attached to the backhoe and just disconnect the shaft end (that way the sealed end won't spin while you are trying to unscrew the end of the cylinder.

Good luck!