Door lock tumbler fell out

[BudTX]

My son came home last light with the door lock tumbler to our '83 K20 in his hand. He said that it had fallen out when he closed the door.

I figured out how to lock and unlock the door by putting my finger in the hole where the tumbler was, and could put the tumbler back in. I can manipulate the lock with the key in the tumbler when I hold the tumbler in place with my hand, but cannot get it to stay in place.

Is there a trick to getting this thing put back together correctly?

Thanks,

Bud