New floor - raising radiator

Bus Tarbox_2

I removed the one-pipe system radiator to install a new subfloor and tiled kitchen floor. That done, now the supply valve is 1 and 1/8 inch below the radiator inlet. I had planned to set the radiator feet in four 1 and 1/8 inch holes through the tiles. It occurred to me that it might be easier to add a 1 and 1/4 inch extender to the riser below the supply valve, and then adjust the radiator above the new floor. Well, the "might be easier" part was until I tried to unthread the supply valve. Holding the riser with a strap wrench, and gently tapping the 12 inch pipe wrench on the supply valve got nowhere. Would a propane torch on the threaded fitting to the supply valve work to loosen? Or should I scrap the potential catastrophy of a broken riser, and just drill the four "radiator foot" holes?
Thank you,
Bus

bob young

do not set radiator in holes !!!

for a professional plumber that is a less than one hour jobbing call. remove valve, remove tailpiece spud from radiator and extend connection w/ new valve and connect radiator,check grade and test. collect cash and end of story.