Thank you all for the help. Dave, you were right on with your description. It took me about 2 hours(by myself) to figure out all the geometry and get the rod attached. I ended up:
1. Removing the spring (only one on my '58).
2. Unscrewing the vent hinge plates to get enough access.
3. Pulling the whole mechanism out to see how it worked.
4. Removing and cleaning up the cylinder.
5. Loosly reattached the hinge plates.
6. Feeding the rod back in, tighing everything up and reinstalling the spring.
The hardest part was to get the hole in the cylinder aligned with the rod. Look, try, turn it a little, try again, etc. GREAT PLEASURE when it went in!
The recovered dash rail (I used black everflex) is on and what an improvement! And the scuttle vent opens and closes!