Guys sorry it's me again. Tried using stilsons, can't get a proper grip on the mildly rounded nut as there isn't enough surface area. Tried hammering the 4 sided nut, both by itself, and tightening the loosened nut and trying. Still can't get it loose. Don't know how you guys make it sound so easy. Called up R E Customs and they wanted $160 to remove the HICAS even though I had the bar already I've tried so long already, it wouldn't be worth it if I had to pay that in the end...
This is becoming SOS. Please help.