The process is fairly simple.
Things you'll need are:
A GS-150 (obviously)
2 clips. You can easily find them at a computer market.
A hammer and nail. With those just make 2 holes in the tappa.
And one here
Then put the clips in these holes.
Replace the old washers with new ones and put tappa on. The clips should go like this.
And tie them up.
And viola! you're done. And this alteration isn't visible from afar.
If you can't find these clips like 2 of my buddies you can use telephone copper wire.