63 Dodge Dart, now let me see;)

re an external slave..... we've done a few cable to hydraulic conversions and often find there's not room to mount the slave so it can push on the release arm. we found wilwood do a 'pull' type slave cylinder, it's really slim and has the pull rod one end and a stud for mounting the other. it allowed us to fit a slave the other side of the arm which got us out of trouble. plus i think a hydraulic release bearing is a ridiculous idea from a servicing point of view.
neil.
https://www.wilwood.com/mastercylinders/MasterCylinderList?group=Slave Cylinder