Looking for QD on the sling, 2 point? Drill a hole where you want to mount something. There are rail kits from MagPul, Nordic, Noveske and others to let you mount rails with just properly spaced holes in the handguard. Some have thread locker on the threads with basically T nut on the inside. They are elongated so they won't rotate. Then again, you can buy a machine thread sling stud and get a T nut and nylon washer from ACE for a grand total of about $5/unit.
Or, save all the hassle and just buy a
Hogue Cuff