I searched the forum for info in fitting central locking  to pre 78 C3 
 Here is  my version  one, of how to do it  
I would like to fit two actuators to each door have some back up and do away with the key entry
One actuator is mounted on the cover  to access the door internals
the other will possibly be inside the door 
Still working that one out.
I could go with coping the later 78 up idea for electric locking.
mod to actuation rod 
 assembled unit 


Bfit