Flare Tip Evolutionary Moment - Q2 1961

I picked up two Flare Tip "G2" razors that looked identical at first blush.  But upon close examination, there was a difference in the design despite the fact that they were both G2 Flare Tips! 

See the one on the left with the wider ends on the baseplate? 
Contrast that with the one on the right with narrower ends on the baseplate?


Here's another view with the missile bay doors open.  On the left you can see there's a pretty narrow tolerance for the center bar to move up through the base plate, but on the right, there's a huge gap with a wide tolerance on each side.


Otherwise, these are identical G2 flare tip razors.  Both made by the same company in the same quarter, yet there is a distinctive manufacturing difference!  I checked out my 1940s Super Speed and it had a tight gap.  I checked a flare tip from 1970... it had a wide gap, like the one above right.  I conclude that design change happened in Q2 of 1961 (which was also a great time for Chevrolet Corvettes).  It seems that razors produced EARLY in the 2nd quarter had a tight gap, but before June of 1961, Gillette decided to open up that gap for more center bar clearance, and continued with the wider design (at least) through 1970.  Exactly WHEN they made this change in the 2nd quarter of 1961 will likely remain a mystery.  Did it happen in April?  May?  June?  We may never know.
-  Bax