This shock is the front suspension shock for the track on a 94 580 ext cat. I have got the shock off the skid and what to change it but need to switch the spring over to the new shock.

do you have a threaded collar at one end or is it just rings around the shock body.if threads you could just back off the collar ,if rings you can use a shock spring compressor . witch will also work on the threaded collar

I was in a pinch once and did it using about a dozen zip-ties. Just wrap the ties around several coils at a time and just keep snuging up the ties a little at a time, untill there is enough tension off the spring to remove the cup.