Stephen, all credit to you in attempting to find out more but I suspect that wishful thinking is the best you can hope for.
The chance of records remaining are slim - the police force in Glasgow has undergone a number of iterations since they were supplied with that Enforcer in 1975. Assuming it was destined for the City of Glasgow Police, they were amalgamated into Strathclyde Police that same year and more recently all of the regional police forces in Scotland were merged in 2013 into the single force that is now known as Police Scotland. An act viewed by many (me included) as a predictable retrograde step, but when are the decisions of our elected representatives ever based on good old common sense!