Noisy vibrating shifter

Well, I do have a nasty driveline vibration that I have yet to figure out, so maybe that's the real problem. Thanks for that suggestion RRR--funny how I never put the two together in my mind. I've spent quite a bit of time getting my pinion angle corrected, but that didn't quiet things down. Went from a poly trans mount to a rubber one--that helped address the symptom but not the cause. I'm wondering if my driveshaft is too short (slip yoke too far out) or bad front u-joint (already replaced the rear). The Victory driveshaft and all components are new ... Driveshaft balanced... I'll be glad when I get to the bottom of that issue because it drives me nuts.