1966 C10 Grill, Headlight Buckets, and Grill Support Panel Fitment

[TxCajun]

I've been doing a little more digging, and pulled these images from the https://www.classicindustries.com/ catalog.

The main differences that I'm seeing from these two photos is the hole patterns in the areas where the headlight buckets attach.

Classic Industries catalog says that the second one fits 1960 - 1963, but I've read comments from others that the 1963 is different.

I've also seen comments that the relief areas at the bottom for the frame rails are also different.

From the headlight bucket mounting hole patterns in these pictures, I think my 1966 has the earlier version of the Grill Support installed.
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