Check the end of the gland nut to see if it has 2 holes, about 1/4” diameter. If its that style, it will be screwed in. You will find it is standard left hand thread, the ends can some times rust a bit making them really tight. You also have to tighten them up a lot to get them to seal some times.
What i do, i get a length of bar and put it through the mounting hole on the tip of the cylinder to hold it down, i get someone to stand on it. I then get a large wrench (we call them stilsons here) and haul on the gland nut to get it to crack. Be careful of the chrome bar, if you slip while pulling on the wrench, you can slip and hit the chrome bar. Cover it with a news paper or 2 (a full news paper that is).
You may even need a pipe on the wrench to get it to crack. Give it a go, if you have any more problems just give me a yell. Once you have that off, the seals are a snap to replace.