When I read the lives on the mechanics of the 1950's it strikes me how they had to know how to " spanner" the whole car. Pete Byant tells in his book about being able to strip and maintain the Climax four cylinder engines for example.
All that engine work stopped when the Climax V 8 's then the Cosworth engines arrived and the builders took over all engine maintainance, done back at the factory.
But one peice of precision engineering stil got maintained trackside and remained a team rebuild responsibiilty - the gearbox. I have seen many pictures over the years showing a mechanic toiling away at the back of the car , trying to keep everything clean amidst the general paddock mess of yore.
I have the impression that each team had one trasmission expert who worked alongside the normal car assigned mechanics like Alec Stokes of BRM. How many other teams had a gearbox specialist?