From a practical standpoint I don't believe any 60-66 Chevy gauge panel will fit in any 60-66 GMC. The opening in the GMC dash is wider and shorter. In the entire series GMC's only had two types of panels, the earlier metal pan with a small cluster in the center, and the later design with a plastic bezel.

Here's a link showing the different types:

http://www.6066gmcguy.org/cluster.htm

Depending on your budget, here's a very expensive restored unit:

http://www.bowtiebits.com/store/sto...amp;Category_ID=4&Sub_Category_ID=74

Here's an outfit that makes custom GMC panels. Just click Chevy/GMC trucks, and keep clicking until you get to the GMC entry:

http://www.boeseengineering.com/

And here's a thread showing different custom ideas:

http://67-72chevytrucks.com/vboard/showthread.php?t=360089&highlight=dash+panel

1960 GMC 1/2-Ton Pickup Truck
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