Barrel question, advice/help needed...

[Iminocca]

My next AR build will be a pistol, time for something a little different, and I realized I have an old Bushmaster upper with the 11.5" barrel and a 5.5" flashider pinned and silver soldered or welded...I'm not sure which. Is there a good way to separate the flashider from the barrel? I was thinking about making some longitudinal cuts in the FH over the threaded area with a cut off wheel (not cutting into the threads) heating with a MAPP gas torch while twisting with a pipe wrench. I'll have access to a lathe next month and I could simply cut it off, recrown and thread the barrel. Is there any overly compelling reason to keep it as is? Thanks!

[ar15barrels]

Look for two little discolored areas where the welds are before they were ground down and the whole barrel was parkerized.