I've rebuilt fox IFP shocks for the JL series jeeps. The ones for the JK and TJ may be different.
On the JL shocks, there is a little little screw that holds the nitrogen charge in. When you unscrew this, the pressure bleeds off.
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There isa tool to refill this, but it's expensive, and impossible to find. I drilled and taped threads to accept a Schrader fill valve.
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The dust cap pops off and the internal snap ring is all that holds these things together.
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The internals of the shock are not much different than a fox 2.0 remote reservoir. The piston is different. But maybe interchangable.
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The shims are the same except for the serrated bleed shim.
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You can easily change the shims to change the way the shock performs. It's not rocket science, but tuning is an art. Hopefully this helps your understand what you're getting into.