Thanks Dan , sounds like a plan . The only bit I'm unclear of is the part where you initialy hang the car and clamp the piston , I'm fine with that . Then depressurize everything to pull the head to take the measurement to the stop ring , in doing this you would destroy the packing no ? Everytime I have repacked an Otis welded head jack I have had to pull the old packing with a T-bar with a screw end. If you have to do this to get the measurement then when you put everything back together and re pressurize to remove the hoists and clamp to let everything back down to land the car on pipe stands don't you have oil pissing everywhere due to the damaged packing ?
Also I guess the sleeve has to be made by someone like eeco as I would have thought it needed a machined Finnish similar to a piston in case it slides up and down in travel ?