MY 1999 2500 is blinking the odometer, clock and overhead console. they blink 30 times then stop for 1-2 count then start up again. It starts and runs fine.
If I key off I hear the clicking for another 6-8 times before it stops.
Batteries are new and charged.
I appreciate a tip on what to check.

 

Grab the appropriate year service manual for your truck from this thread. Wiring diagrams are in section 8W. Follow the power path for those circuits, and see what you find.

 

When did this start?
Was it OK before? and before what?
Have you installed anything on the truck? New Radio, Alarm System etc
I assume its diesel since "batteries" which you said are OK
Have you had your alternator tested?