Typing while Bob was posting
...........But for sure as a general rule for Mustang production we cant say Dearborn only used one style, San Jose only used one style, and Metuchen only used one style. Thats just not correct.
Make sense?
Depends on how you phrase the statement. We can argue about the application of "never" "only" "always" and I think we will both agree most of use leave those words out of responses at the same time we often make, what could be understood as basically the same comment by using the word "where". But enough of the English language discussion. Not to be argumentative and just continuing a respectful discussion, we be rarely can say "only" but in maybe a few processes or parts since there is always a possible variation or mistake even.
Based on research we can say typically, usually, the vast majority of the time and so on when we discuss these details or when giving guidance to people that don't have a specific part and are looking for the best and most complete information. If we find that one plant used or was supplied by than more than one provider for jacks, lets see when those different products were used on the line and in turn we should be able to identify batches and runs so that we can better help and guide others to a better and hopefully right choice.
We have to be able and or willing to collect multiple data points from unrestored, original cars, compare them to others, while considering when they were completed to look for patterns if one possibly appears. We should by now accept and understand that suppliers didn't ship parts individually one at a time so there will be supporting evidence from other cars built the same day or week of an anomaly. We all need to let the evidence guide us rather than letting us try and bend it to our current understanding alone. NOT suggesting that this is what anyone here is doing. Just a general statement.
This might be a good subject to start some plant by plant surveys to see what we can collect as we have with many other subject/parts, to see what additional understanding can be discovered.