Thanks for all your efforts to retain the correct cap. The correct design cap is crucial to the factory look, which the photo of your blue truck proves. As you already discovered, GM never had a one piece 16" 8 lug wheel with clips, we must create our own. Here is a similar link on the subject.
http://67-72chevytrucks.com/vboard/s...e+rims+hubcaps and
http://www.laroke.com/larryk4674/smo...er/hubcaps.htm