NOTE: the first two posts were split from another thread so that the specific topic could be focused on without taking the other thread in a new direction.
Reviewing some older posts for details in painting my engine but came across another would-be running change or frequently unknown (or unsure) fact about the Rear Package Trays of the Coupes. I wonder how much interior options play into the use of the "screw or no screw" detail.
Marty uploaded other pictures within this thread asking about the strip (seen to the right of the screw in this image) : http://www.concoursmustang.com/forum/index.php?topic=18684.0
It looks as though the strip or molding and the use of the screw go hand-in-hand on these two examples at least.
I will try and link some of this information to this thread, it may be initially tough to follow this train wreck of thought I got derailed onto...bear with me. Maybe it's the coffee speaking 
A11 - If you've ever wondered what the rear package tray screw looked like - here it is
Continuing my thought, certain parts of this thread stood out (when viewing the scheduled build dates of the various vehicles that have been discussed this far to date ) regarding the rear package tray "screw/no screw" and now the added details of the reinforcement strip, then any attempt to align the dates the MPC discusses (John's post with MPC images in other thread and re-posted below again to assist in context of any point(s) to be made).
The Scheduled build date of Marty's example is stated as being September 26, 1966 which is long before the otherwise stated change-over in January, 1967...is anyone else "with me" so far?
My 65B example (Coupe with Deluxe Interior) had neither the screw nor the "Reinforcement". My 65B Coupe has a lip bent into the metal or the quarter trim to tuck it UNDER the package tray. I believe the 65B uses the padding of the upholstery to bridge the gap that the "Reinforcement~" uses since the standard interior (65A & 65C) uses a different quarter trim WITHOUT any upholstery added. This would perhaps help? I believe the "After 4-1-67" date, the quarter trim parts were changed to no longer need the "Reinforcement~" since the rear edge was re-designed to fit OVER the rear package tray.
Is this sensible or did I miss any details or assume to little or too much?
RE: quotes within this thread and in other thread:
As a follow up to this question. Looking at my collection of pictures it appears that the change to the visible screws started between 7R146875 and 7R1680xx.
Of course this is not a hard line for the change. We don't know exactly when each of these cars were actually built. Just gives us a general idea of early December to mid Jan at San Jose.
Just another of the hundreds of running changes that make restoring 67s so much fun 
John
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Marty, thanks for sharing.
Regarding the molding, that is what Ford calls a "reinforcement - package tray trim panel end" and carries a C7ZZ-6546562 part number. The 60-68 MPC says "before 1/3/67 " and in another area says "before 4/7/67". Yet another note says that the "top edge overlaps package tray from 4/7/67"
There is no reference at all in the January 67 dated 1967 one year only MPC
John
