I have a platform B, based on how it attaches, I don't believe that platform k would be able to direct to raised rail on the BS. The mount sits inside the outer frame. So on platform K it is 49" across the mounts are set in about 2" on each side which brings the mount for the bracket outer edge at 45". However the bracket to the raised rails has a center point another 1.25". That makes the center point 42.5" across at its max. The back of the BS wouldn't be an issue but you'll need a shorter antenna to get it far enough back, and where the front ones land has a chance of being extremely tight or not fitting at all.
