Harmonic pulsation / Vibration?????????

Keep in mind that i have already tried, checked and replaced every other aspect of my exhaust...which led me to believe that it is the flowmasters. The vibes were the same with a boneyard 318 from an 85 new yorker or my built 340 w/solid cam.

An exhaust resonator may also help at the expense of more back pressure...so I'm told. My Chrysler's exhaust is downright complex and it's quiet as a church mouse with zero drone, ever....