Distribution Plan
When you order your Master Power Brakes power-booster package, whichincludes the master cylinder, you have choices. Optional is a GMdistribution block, which includes a brake-pressure warning-lightswitch. This is a nice looking bolt-on that functions well if you aren'tconcerned with originality.
If originality is important, you can opt for the factory distributionblocks for 1967-'68, which also have the brake-pressure warning-lightswitch. The warning light comes on whenever there's a pressure loss ineither the front or rear braking system. Pressure from the working sidemoves a pressure differential piston in the direction of the "nopressure" side, which closes the switch and illuminates the light.Whenever we correct the problem and bleed the brakes, we need to createa pressure change, which moves the piston back to center, canceling thelight. The pressure change comes when we open a bleeder slowly on theunaffected side. Pressure from the affected side returns the piston tocenter.
Here are three examples of brake distribution blocks. The four-wheeldrum-brake distribution block for 1967-'69 is "A." Front-disc brakeapplications for 1968-'69 received "B," with a built-in proportioningvalve. For 1967, the proportioning valve was located above the rearaxle. The Master Power Brakes' version is "C," which works well forcustom applications, where originality doesn't matter.
This is a bird's-eye view of the Master Power Brakes distribution block.
The Master Power Brakes distribution block can be mounted at yourMustang's inner fender using spacers, or you can use this bracket fromthe kit, which provides a mount that ties it to the master-cylindermounting stud at the power booster. | 
Master Power Brakes provides this brake-pressure warning-light switchlead in the kit. |