I wanted to provide some info to help narrow that 'sometime after May' window. My San Jose scj mach 1 (9R02R1777XX) was built on May 22, 69 and had the 3AA Trim code...and obviously the walnut wood.
Thanks for bringing the subject back up to the front so we can provide a little more information after some focus on the subject
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- Looking at
San Jose built cars Here are some of the examples I have. Listed by real build date first
Jan 8th 69 - 9R02R1315xx (interior code 3A)
Feb 12th 69 - 9R02M1433xx (interior code 3WA)
Feb 21st 69 - 9R02R1479xx (interior code 3DA)
March 24th 69 - 9R02S1560xx (interior code 3AA)
March 25th 69 - 9R02R1583xx (interior code 3AA)
Apr 7th 69 - 9R02R1532xx (interior code 3W)
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Change over date or period seems to be a bit more irregular at this plant.
Looking at
NJ built carsHere are some of the examples I have. Listed by real build date first
Feb 24st 69 - 9T02R1922xx (interior code 3D)
Feb 24st 69 - 9T02R1727xx (interior code 3DA)
April 22nd 69 - 9T02Q2058xx (interior code 3A)
Note: Don't have a ton of NJ examples and 9T02R1727xx is the only one I have with the three digit interior code. Could it be a typo on the Marti? Don't know but the example appears to be out of what the others would suggest the pattern is currently form only my stuff
From buildsheets
9T01S186xx with a 07B scheduled build date has a three digit interior code
9T02H1754xx with a 18B scheduled build date has a two digit (3A) interior code
9T02R2817xx with a 23D scheduled build date has a three digit interior code
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Dearborn cars - Appears that we may be able narrow this change over period to a specific week so far but looking at other plants it may be too early to assume this is a hard change over.
Dec 13th 68 - 9F02M4800xx (interior code 3W)
Dec 20th 68 - 9F02R1430xx (interior code 3AA)