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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