I have fitted a Stanza centre console handbrake lever to a 1600.
The cable exits the cabin at the junction of the floor pan, trans. tunnel and the front of the rear seat platform.
I made a pivot box and lever to mount onto the chassis rail and the handbrake cable pulls on this lever.
The rear cables connect to the end of this lever with the standard balance bar arrangement.
From memory, it would work OK with the rear drums but I already had the R31 rear discs which required a custom made rear cable anyway.
The standard 1600 rear h/brake pivot and lever is of no use where it is welded to the body.
The custom pivot box was the result of 2 prototypes which were too weak.
The current one has survived for 5 years now
There is a lot of tension put on that linkage when you yank on the h/brake