Thing the answer to all three questions is the same
Yes there may be if someone took the time to document and offer for review those findings but at this point don't know anyone that has focused specifically on that. None of this comes without effort, time and dedication. Answers don't always come quickly as today's users of the internet expect. Most answers start with an owner with a need
Recently, in other threads, this very thing has occurred (e.g. vacuum reservoirs) Though we haven't come up with a definitive answer to the "changeover date(s)" we have observed a general direction of the running changes of those items. All such data needs to be collected from ORIGINAL build vehicles and confirmed at least 3 times for each running change at each assembly plant and options, such as Air Conditioning have to be considered with the data collection. This can be a daunting task since Heater Hoses were one of the first things replaced, along with the belts and spark plugs/points/oil etc., ...nobody took notes of such things back when these cars were 2 years old or so.
From my observations the white hoses are most typical early . The red and yellow hoses are a typically much later variation (March 67 maybe) with yellow being most predominate May/June.
Observations of restorers and/or judges, such as Bob Gaines, Bob Perkins, Tim Lea, and so on, are a great source of original build information. They have probably seen more unmolested cars that may still have the original hoses on them. Their advise would be far more accurate than any parts vendors supply catalog, trust in their experience and combined knowledge on such concerns where a definite answer seems to be impossible to find.
Better yet, begin the research yourself and share your findings here. "Rules" are not always "correct" and with enough evidence, rules can and have been changed on such details.
Richard
