Remove seal cap
Remove snap ring
Remove shaft assembly
Blow IFP out of cylinder with shop air into a rag in a trash can
Disassemble shaft assembly (keep parts in order)
Replace seals in seal head and wiper cap
Reassemble shaft assembly (torque nut to 25ft-lbs)
Replace IFP oring
Grease IFP oring
Install IFP into body
Set IFP depth with shaft assembly to oring on seal head (release air from valve as you set IFP or it will just push back out at you and be incorrect.
oil shock to 1.5 inch from lip
sink seal head with shaft bottomed out on seal cap and let oil/air flow out of body then push complete bottomed out assembly into the body.
install snap ring
clean all oil out of body
charge shock to appropriate PSI
install seal cap to seal head.
verify shock bottoms out 100%. if not you moved the IFP and it will hydraulic on vehicle.
If shock bottoms.
Clean shock again
install on vehicle.