I am banned from that site, so I can not view the photos, but I would like to see what you are talking about. The only factory holes I am aware of on the light-duty Chevy/GMC trucks are:

1. 4-speed tranny shifter ('60-'66)
2. 4x4 transfer case shifter ('60-'66)
3. tranny e-brake handle (early 60's)

Tony Smith
4-5-6 Chevy Trucks
501 Scott Avenue
Kansas City, KS 66105
913-207-7789
[email protected]
Photos: http://www.flickr.com/photos/4-5-6chevytrucks/sets/
Custom Parts: http://www.flickr.com/photos/4-5-6chevytrucks/sets/72157627022818563/
www.4-5-6chevytrucks.com