94 Vert dashboard rattle----speedo?

[45guy]

I've got a plastic-y rattle coming from (behind?) my dash. I've tried holding and pressing and pushing just about anything in front of the driver trying to isolate the noise but I'm running out of things I can reach while driving. Ah yes---only rattles while driving, not even while parked idling.There was a time when this might have been a symptom of a dying speedo cable...make me smart, guys---this noise is buggin'.