Pre LockTite days (or in high temperature applications), using a small jamming set screw behind the locking set screw could be used. One just needs to remember to remove the jamming screw and loosen the inner, before trying to adjust.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.