1974 Duster power brake master cylinder push rod needed.

You mean this collar? I just didn’t include it in the first pic because Inhad just pulled it.

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Thanks for the updated photo. It looks like the collar on your shaft is closer to the end than mine. My collar is 1 9/16" from the diaphram (rear) end of the rod. I think this measurement is critical for the proper operation of the brakes. What is this measurement on your rod? Is this collar adjustable for the length of the rod, or is it fixed in its place?