No easy way to tell. No part numbers will tell. Shocks would give an idea (original color of black cases or maroon) but they have probably been replaced years ago. Springs would be hard to tell 40 years later. And, one could get HD suspension without the rest of the Go Pack. Radiators could be 2 core OR 3-core without indicating true Go Pack, most were 2-core. A fan shroud could indicate Go pack,, but HD cooling could be gotten w/o Go Pack as a separate option. 3.54 posi rear COULD indicate Go Pack on a 4-speed and 3.15 posi on an automatic, but again, could have been a separate option. Best to look close under trim of hood, cowl for evidence of original stripes.


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