You've prolly figured this out already. You're on the right track. It's easy and not easy..Easy part: Put the barrel in a vise; get a long steel punch or screwdriver that fit through the middle holes in the brake body, put a 7/8" wrench on the jam nut. Now the Not Easy part, at least as far as other muzzle devices I've R&R'd: the nut can be super tight against the brake body. I'm talkin' lug nut tight. Heat the brake, nut, and end of barrel with a heat gun or torch until too hot to touch. You'll use the punch or screwdriver in the brake body to apply loosening torque while simultaneously turning the jam nut in the opposite direction, as if you were tightening it onto the barrel. Reverse directions with the punch and wrench and the nut will literally SNAP when the threads let go, There was no threadlocker on mine just a ton of preload, I estimate 50lb-ft to break the nut loose. Take the jam nut and brake body off, degrease the threads, reassemble with Rocksett or similar; it'll be easier to keep the brake properly aligned, or "clocked", while you tighten the jam nut. Interestingly enough, Ruger sells this brake on their website and the oroduct pic gives you an idea of how it goes together:
http://shopruger.com/searchprods.asp
