Disassembling the power steering cylinder assembly (1975 Industrial 20) / 135

[MFIndustrial20]

I have a 1975 Massey Ferguson Industrial 20 (similar to 135).
Today I was trying to rebuild one of the power steering cylinder assemblies, and for the life of me I cant pull the end-assembly off of the shaft to remove/replace the seals (which I have already picked out). I've already knocked out the pin, so it should come off. It's probably been on since the tractor was built in '75. What am I doing wrong? Do I need special tools? Should I get out the MAP-gas torch to heat it up?
:confused3:

 

[anglia]

i have a 175 massey just did this repair, i put the cylinder in a vice to hold it took the 4 . 5/16 bolts off that hold the cyn, together, just tapped on each side with a rubber mallet, and it will come aprt, just the orings are holding together