Hey Awaino - There have been a couple of instances similar to yours where after the new odometer gears were installed the tumblers suddenly stopped again. There is a good write-up on installing an additional very small washer on to the odometer drum during reassembly to keep all the gear teeth tight and synch'ed. The description on sizing the washer is toward the end of the procedure.
To get the speedometer/odometer back together only to have it stop working once again is really aggravating. I had the same thing happen but mine had quit a second time because of the destruction of another brittle gear that I should have replaced during the initial tear down.
1984 ODOMETER REPAIR PROCEDURE
Good Luck, Michael
