Join Date: Jul 2017
Location: Long Island, NY
For bars like that, I'm sure you'll need new cables. The stock lines can work with lower bars or slightly higher but any more than that, there won't be enough line. I tried out a set of flipped clubmans a little while back that were only 4.5" high/27.5"wide and even for those the front brake line just barely worked and the cables were a bit tighter than I would've liked.
As far as the tabs, I would drill the holes. I won't preach one way or the other because on my scooter I just grinded the tabs off and they hold well, but I'm not going 60+ mph on a scooter so I am not as worried about it. I would spend the extra time to measure and drill out the holes for piece of mind.