I'm trying to remove the fake flash suppressor from my Poly Tech M14S. The set screw is out and the castle nut is loose, but I can't get the flash suppressor to budge. The only thing I tried so far is soaking with Break-Free and WD40 and then hitting it with a mallet. What next? Should I try heating it? If so, what should I use to heat it? Any help would be appreciated.