Just got done doing this. Once I had this piece off I took a dremel to the bolts holding the arms on vs cutting the arms themselves. It was a serious PITA but the seats do not have a soft spot in the padding once you mount the plate back on.
Black 2011 JKU Rubicon/ 6spd w/5.13 gears/ 5.5" RK X-Factor Mid Arm (3.5") Springs, RRD Shocks/ Poly Inner/Outter Sleeves and C-Gussets/ Reid HD Knuckes/ 37" Nitto Trail Grapplers on 17" MB72s/ ACE Flat Fenders/ JCR Front Stubby Stinger, Rear Stubby Bumper and JCR Deluxe Sliders/ Warn 9.5 cti w/Syn line/ OR-Fab Swing Away Tire Carrier w/Fuel Can mounts
Oct 2012/Dec 2013 JKOTM