Thought it was about time to survey and share our findings on when the change took place from the 9" third member designed without a fill plug to the version with a fill plug that took place during 1967 production. The results will be linked to each of the three 67 running change threads once established. This will also help with the 9" rearend fill plug location discussions.
As usual we need the casting date and if it has or does not have the fill plug located on the drivers side (once installed) of the main body of the third member. If you happen to know what car it came from that information as well as the real build date those would also help allot.
Thanks for your consideration and to those that participate in this effort
++++++++++++++++++++++++++++++++++++++++As of 10/24/2022
Latest cast third member without fill plug - 6J2 (Do have later built cars with no fill plug but no casting dates from them)
Earliest cast third member with fill plug - 6M16
++++++++++++++++++++++++++++++++++++++++Picture below shows the no fill plug version in the upper lefty and the fill plug version in the lower right
Picture shows the location of the casting date for the 9" in 67