I'm not sure what you're talking about as far as clearance is concerned.
Are you referring to the extra 3mm of stroke? If so, I've got plenty of rear tire clearance with the OE 2.6 tire. Looks like even a 2.8 would fit, but I personally have no plans to swap out to a bigger rear. I like as much front traction as I can get, but like the back end to slide around when I want,
If you were referring to clearance around the shock itself, there's no problem there. It fits without touching that brace.
I just installed it yesterday and today it was a rainy day here, so I'll be riding on it for the first time tomorrow. Ill cut it a little slack because it's an air shock, but I like the shock to break into its travel sooner rather than later, and I like the tire to follow the terrain instead of bouncing all over hell's half acre. Where I'm riding tomorrow has some areas where you need to bounce from rock to rock, so I'm hoping the X2 gives it more pop. If it does that, I'll be willing to be more forgiving on the other stuff

Keep in mind however, that the X2 I'm using came off my Firebird 29, ie it's been valved for a bike with different wheel size, leverage curve, and of course, one that weighs over 20lbs LESS. I'm anticipating the valving being a little weak. If it works as-is good enough to keep, I'll just send it off to have it re-valved, and put the incoming DHX2 on the Pivot.
Either way, I'll report back here how it works
Edit: I just went out in the garage and let the air out so I could take pics showing the clearance at the tire, and around the shock. Hope this helps you.
View attachment 26437View attachment 26438View attachment 26439View attachment 26440
Just to be clear, these photos are with the rear suspension totally bottomed out