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

[TxCajun]

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

My truck was a ranch truck for most of its life and then parked in a barn in the late-90's. The front end suffered some damage somewhere along the way and as I've taken it apart I've noted that several sheet metal components were not the originals. I also noted at disassembly that the grill was only held in by a couple of bolts.

I'm currently in the sheet metal working/straightening and primer mode, and I'm test fitting parts. I think that the headlight buckets are the correct parts because they are stamped "CHEV-TA SAE H64".

I have two issues:

1. Where the Headlight Buckets are supposed to bolt to the Grill Support Panel, the two holes towards the outside of the Grill Support Panel line up reasonably well, but on both driver and passenger side the third bolt location is off by roughly 1 inch at a 45 degree direction See location of blue tape in the close-up picture.

2. The Grill seems to be too high in relation to the Grill Support Panel, and the top of the Grill above the headlights is actually rubbing the underside of the Grill Support Panel. See cardboard marker indicating the area in the other close-up.

Before I start modifying hole locations, I'd like to understand the problem.

A. Is it possible that the Grill Support Panel is from an earlier year than the 64-66 models which are supposed to be compatible?

B. What should be the approximate dimension of the gap between the top of the grill above the headlights to the underside of the Grill Support Panel. (It looks like the Grill could be lowered up to 1/2" before the lower part of the Headlight Bucket begins to interfere with features on the Grill Support Panel.)

Thanks for your help and advice!
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[65Custom]

I'm not 100% sure on this but I have heard that 60-63 are different from 64-66 grille supports and what I have heard is it is related to the grille mounting.

I would like to know if there are any other ways to identify the grille support itself other than the mounting holes.

AMD does sell the different versions and in the pictures you can see different holes in them for girlle mounting

[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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