I’m not too familiar with these spacers for the PDB master cylinder?
Which side goes to the rear of the master? I’m assuming the round side and the flat side goes to the booster?

Also I have three gaskets? Which gasket is correct for this application and does it go between the rear of the master and the front of the spacer.
Looked in my FSM and it wasn’t much help?

Thank you!!

top foam goes goes behind the master cylinder , the bottom ones are for the booster to firewall , not sure which is which , does your firewall use a backing plate on A body ?

as far as the top one ??


Here's a bump , long time since I messed with that on my dad's 72 Duster.

With the top gasket that fits between the master cylinder and the booster, the solid gray side would be against the master.

The gaskets in the lower pic fit between the booster and the firewall. With the two gaskets in the lower part of the picture, I would be surprised if the bottom two gaskets are not the same, but merely flipped over to have the offset leaning in the other direction. In real life, it probably doesn't matter which direction the offset faces. That larger off set hole gasket is probably only an option to seal the booster with the linkage that wouldn't fit through the round hole of the top gasket. With the longer, larger off set hole, the gasket can be turned slightly, placed over the linkage, then turned straight so the gasket will still seal the hole. If your brake pedal attaching rod is a single rod (as compares to the offset linkage in the picture in your manual), the round hole gasket would work fine. If you have the rod with the offset linkage (like the picture in the manual), the round gasket probably won't fit over the linkage, but the gasket in the lower part of your picture can be turned to fit over the linkage, then turned to match up with the bolt holes on the booster.

Which gasket you need at the firewall depends on the rod design between the booster and the brake pedal. You should be able to identify which firewall gasket you need by looking through the firewall hole from inside the body. there is either a round hole in the gasket, or the elongated hole in the gasket, and that should be visible from inside the car. .

Thank you. It does use a bracket at the firewall.