Auto Glass: Back window block size, 1957 Desoto 2 door hard top /1957 Chrysler / 1957 New Yorker

Question
I am trying to locate a replacement back window for a 1957 Desoto 2 door hard top. (same as 1957 Chrysler 300C and New Yorker 2 door hard top) The folks I have contacted have requested the "Block Size". Not sure what this means.
Or if you know of a supplier that could provide a window I would appreciate.

Thank You
Scot

Answer
Hi Scot,

         Nice Car!! There are two possible options on this back glass.

1957 Desoto 2 door hard tops and the 1957 Chrysler 300C / New Yorker 2 door hard top.

Nags Part #  B462 Includes Models C76,LC3-H LC1-L, LC2-M

Block size Measures   32 x 74

Nags Part #  B463 Includes Models C75-1 & 2, LC1-L, LC2-M

Block size Measures    24 x 72

Nags stands for National Auto Glass Specifications

Block Size means the glasses Measurements at its Widest and Highest!

So to determine which back glass you need, Measure from where the center of the back glass would be and the height should be 32 inches or 24 inches

And although you can mistake a 72 inch wide back glass for a 74 inch with the Curves and all

There is no way you can mistake a 24 inch high back glass for a 34 inch
  
I did call Pilkington Classics for you and they said they do not have any of these parts and could not get one for me.   
         
I hope these other guys have one!!          
         Hope This Helps!  Derek =D

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