I was planning to go to the local scrap yard to purchase a piece of thin stainless steel to make a clip to hold the parking brake valve control arm in the OFF position. But, this evening my eye chanced upon a stainless steel hose clamp, and I realized that it was made from the perfect piece of metal. 1/2" wide, and just the right thickness. So I hacked a piece off, and bent it into a clip.

The clip. It was much easier to make than I expected, as I started with a piece of material already the correct width. Stainless steel is a pain in the butt to work with, so I wasn't looking forward to making this.

Here you see the clip clecoed in place. Tomorrow I'll countersink the holes on the bracket and rivet the clip in place.