How to rig this up?

[Old_iron]

The short: I need to have a functional parking brake, it doesn't matter if it's original.
The problems:
1. Apparantly the brake cables are shorter than what came in my 68 GMC. (The rear diff is from a 72.) They dont reach the frame mounts. So, essentially the mounts are in the wrong place. I bought some simple mounts from LMC that you can see in the pics, although they dont have the standoff that the stock ones do to clear the frame.
2. The primary cable (I bought the brake cable kit from lmc) is too short. Probably a foor or more. Can I buy a cable from Home Depot or such and crimp the ends?
3. The support rod has no place to attach on the frame. I know later years a bump out with a round hole in the frame, but my truck does not. As you can see there is a slot of sorts but that's it.

The question: what would YOU do to get this truck set up with a parking brake?