Need Help - Looking at 72 GMC Sierra Grande

[mgm60]

I'm looking at buying a 1972 GMC Sierra Grande 1500 and have been searching this site for clues on how to identify Cheyenne Supers and Sierra Grandes. This week I will be looking at two GMC trucks and neither of them has the SPID. Both are highly optioned (factory air, tach, etc.) have headliners, lower woodgrain exterior trim and rear cargo light but don't have woodgrain dashes or glove box doors. Interiors look like they've been replaced/refurbished at some point and neither has the wood grain door panels. I've read on the forum here that some members have bonafide Sierra Grandes without the woodgrain interior trim pieces. And I realize all this trim stuff can be added to make a truck meet the owners desired look and not necessarily be authentic.

Without the SPID, what else can I be looking for on these trucks to verify if they are the genuine article?