Meh, get the sizes of all of the 0-rings in the thing for the reg, go to the 0-ring Store buy a bunch, way cheaper than a dumb kit, get a good brass o-ring pick kit and a nice needle, that's for the one buried down in the hole, replace o-rings, if you don't have the new brass pistons, get them, less heart ache. If you do have the new brass pistons look at the little Delrin piece in the middle, is it concave (bad) or convex/flat (good) I'll bet on concave due to over pressure. Replace ALL of the o-rings, they're cheap because you now have LOTS of them, lube with a good oil, doesn't need to be silicon, regular synthetic won't explode in the gun. I've found that those little suckers on the adjuster like to be heated up in HOT water makes them easier to go on, you'll break a few probably but YOU HAVE LOTS OF THEM. Also order a bunch of Belleville's, why you may ask, measure all of your current ones, right on the edge take an average, if you want consistency match all of the Belleville's so they all work evenly, give them a light polish and a light wipe down with the REAL OIL (synthetic). IF you don't have a digital caliper, Harbor Freight is your friend. You can actually polish up the piston and the mating surface with a leather strop, I cheat a touch a use a VERY fine lapping compound on the strop, it really doesn't take much. Keep the leather in a plastic bag when not in use, avoids contamination. Note, some of the pistons come with the Delrin sticking out about 1.5mm, that is way too high, it needs to be ALMOST flush to get enough pressure out of it. And...on the Belleville's get 100 of them, thicker means more pressure and the thicker ones are rarer on the manufacturing tolerances. Send me a PM and I can give you the numbers I've figured out, or do a search, it's posted here in a few places. Oh forgot get a good tweezer kit, it comes in handy, the ones that stay closed, Amazon.
Good Luck
Hoggie