Cartridge/PFP cap :
That circlip on the shaft is what stops the PFP inner top cap from compressing the spring any further. Not a good idea to force the PFP once it reached the maximum of its adjustment .
Remove the circlip and use the octagonal cap tool to hold it and with a wrench on the PFP shaft unscrew it until the inner PFP cap threads are all out
As you can see there is another circlip at the bottom. This one is responsible for holding the PFP adjuster from moving on the cartridge cap . It's very important to have this circlip set straight, besides holding the PFP adjuster it also stops the steel ball and spring from the compression clickers from falling and sets tension on the spring:
Beneath the circlip there's a steel washer, once removed you just need to push up the PFP adjuster :
I did not use any strong grease when putting it back together because this is all fitted with small tolerances and the grease just makes it very hard to adjust all the parts including the compression clickers. Instead I sprayed everything with Motorex's Joker .