Rear strut tower bar problem

[mrbond]

K, so I received the Nitto rear strut bar a week ago and installed it (note: without jacking the car up). First, I left the rubber pads on and had the bar bolted on top of those. Then, after talking to Garm, decided to take them off. There was a bunch of rattling from the strut towers each time I went over a bump or onto my driveway. I then decided to buy large-diameter washers to distance the bar from the strut tower. The bolt from the strut is noticeably shorter than before I installed the bar.
Any ideas how to raise that bolt up? I have a feeling that if I'm able to bring that bolt back up, then I won't need to put the rubber pads back in and I'll still be able to cancel out the rattling.