Technical 1955 Chevy pickup, what is the function of this rod?

1955 chevy pickup, 2nd series, what does the rod control that comes thru the firewall and goes down to a clevis that is connected to some frame mounted linkage in this pic, I am not referring to the steering mechanism but the rod that is above and outboard of the steering?

 

you mean the parking brake rod? There should be a handle at the top end of it, under the dash.

 

from the parts book

 

Is that what that is? In my truck the rod is no longer there, just the linkage that is mounted on the frame and there is a lever under the dash. So the parking brake operated the front braked as well as the back? Rear parking brake linkage is not functional either

 

Parking brakes are only on the back. There are cables that connect the linkage to the individual rear brakes.

 

Aha, thanks for the pic, that explains a lot, the mechanism goes way to the front and then to the back to actuate the rear brakes, Thanks for the information Squirrel you are the best!