Try adding an once more of fork oil first.I added 1 once more to my '07 FLHTI during the replacement of my fork lowers & it seems to be slightly firmer but still has plenty of compression needed to function correctly.
Progressive Suspension products are great(imo) but;may not make the change your looking for.I've heard of some installing "gold-valves" from Racetech which modify the dampening & such.I like the inexpensive adjustments first.(don't get me wrong...I've spent a **** load of $$$ on my FLHTI w/no regrets

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00 wildglide.