Does this drivetrain play look/sound normal?

[jbtvt]

Just bought a new '98 GS400, 111k miles, dealer maintained, no codes, runs and shifts strong. Body has some scratches and hail damage so I got what I hope turns out to be a good price. It has a pretty severe vibration at high speeds, get noticeable maybe around 50 and by 80 I'm shaking in my seat. It seems load dependent - stronger under accel and decel than cruising. Mounts and CVs seem OK, the vibration damper is a little cracked and I'll probably replace now but doesn't seem terrible



The center support bearing seems to allow quite a bit of play but the rubber is solid and shows no signs of cracking anywhere, so I assume its supposed to behave like this? When I wiggle the front shaft though I hear a noise which seems to be the splines moving around. It looks like a sort of compression fitting to me, anyone know if that's the case? If so, should I try to tighten it up a bit or better to leave it loose so it slides? Here's a video of what's going on there.

https://youtu.be/CVqdMOTHQww