Heres a link for vin and model numbers.
http://67-72chevytrucks.com/Chevyear.html
Also member chipflyer makes authentic SPID repro's. Heres the color code chart.
http://autocolorlibrary.com/cgi-bin/search/search.pl
Link to chipflyer spid's
http://outintheshop.com/2.html
chevy and gmc trucks had vin plate on door jamb rather than cowl.
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