This is a great update for your RockShox 35 mm Sid fork. It works on the c series and d series forks. It has a three position remote lockout. So it's open pedal or locked.
Unlike the original race day damper, the lockout does not get soft on this one. There was a flaw in the first Race Day damper that was corrected with this Race Day 2 damper.
If you have that original damper with a soft lockout this will fix it.
I also have the RockShox Ultimate twistloc available ($60 - usually $130) If you don't already have a remote. Comes with new rockshox grips specifically for The Ultimate twistloc.