Since the new R non LV doesn't have any simple way to do that, we need to know - 1. LV or not. I saw that you have a '23 X2, or was is a '24? 2. Is the shock body threaded at the top of the spring with two locking rings?
If the shock body is threaded, you loosen the top one, and tighten the bottom one. Make SURE the threads are clean, once you gall them your life will suck.
Where to measure, look underneath, pick a flat spot, measure. Note that the very rear on a Talon tips up, measure in front of that taper.
Here's where I measured mine in the rear with a 1/2" Trail Armor skid. This was with the preload fully compressed and sacked out tender springs, it's 4" low.
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