Need some help with Brake issues

Going to try the lipstick idea the wifey gave me some she no longer uses haha.

Here are the master cylinders, the smaller one is the old and the other new. The new one looks like a newer model, and looks just like the one on my dads 70 Cuda.

I adjusted the rear brakes and will give the master a chance tomorrow. Really apriciate the help!
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