I just went through this with my 96 LX. Had the same symptoms. I bled the brakes first, didn't solve the issue. Replaced the master cylinder and its good as new now. Not the most technical way to diagnose the problem, but it worked for me.
Finally got it greased up and took it out on the highway. It's much smoother. I'm hyper focused on vibrations now, still getting a some here and there, but it's much better. Thanks to everyone, I appreciate your help.