American 450 Busmaster Muzzle Brake removal ?

Need some help. Picked up a American in 450 Bushmaster. Would like to remove the brake. Seems simple enough. Back lock nut off the brake then thread brake off barrel then thread nut off. The lock nut is giving me the issues. I cannot find a wrench that fits it well. The flats are very small and then the shoulder of the barrel limits the thickness of the wrench.

So before I start cussing and break something any advice. Anyone successfully removed the brake with out damage to the brake the gun or themselves? Thanks.

I have s en nuts lik this in the past. What I have always done is taken an open end wrench of the proper size and thinned it down on a bench grinder until it would engage the thin flats.

This will probably make a few of you cringe but thats just the way it is....

My Bushmaster didnt have any room the loosen the lock nut. I think Ruger tightened the nut on the barrel and locked the muzzle brake against it. I ran a steel rod through the brake vents, clamped the gun in a vise and twisted the brake off. Bent the rod but the brake did come off and I only buggered it a little bit. The muzzle brake was going in the parts box anyway so it didnt really matter.

Update: I got the brake off. Was a son of ... Ruger told me to use a 7/8" wrench to back the lock nut off should be just snug they said. Well after lots of swearing I came to the conclusion the barrel was more likely to unthread from the receiver before the lock nut would move. Applied heat nope. Let sit a couple days with penetrating oil nope. Was going to go the bar through the brake holes and try to move it. Was hesitant as Ruger gets a 100 bucks for a new brake.

So I figured before that I try tightening the locknut instead of loosening. Has hoping a little movement might even the wrong direction would break things loose. That was the trick. About a quarter turnand it broke loose. But the locknut was turning with the brake. No big deal I was able to turn the brake and the attached nut off by hand. Once it was off It took some gentle tapping to get the lock nut off the brake. There was a large metal shaving between the collar of the lock nut and the brake.

Always the smallest things that make the easiest jobs a pain the asss.

How big do you think the arms are on the guy that tightens the muzzle brake nut ?