Just an odd-ball snippet but here's Chrylser's 1956 solution to a perpetually running dash clock
http://www.rockauto....dex.html#trivia
Go to the trivia bit ( and thanks to Rockauto - a super supplier).
For 1950's Detroit its actually a pretty neat low-cost solution.
My real favourite there is the "Highway Hi - Fi" - If you had one of those in your Dad's car in 1956 you would be just " to cool for school"!