Will it effect the parkerizing of the metal finish ----the black .....if i torch it and bring it up to temp for removal? Im wanting to install a floating handguard and ill need to remove it .......to remove the front sight....

DO i torch it and then just wipe it clean when im all done and every things cool?

DO the companys attaching these attach them after the barrel and brake are finished?

Can i reinstall the brake afterwards --or-- will there be a build up of silver on the threads so i CAN NOT install it back on?

Red hot temp may hurt the park.  

Best way:  remove brake, gas block, bbl.  Blast and repark entire bbl.

If you have the ability to remove the bbl.  (not a fun/easy task, many factors involved)

Lauer will parkerize bbl for $55.