Ok, now I am confused. So Capt. I looked at your link (
http://brochures.slosh.com/index.shtml?1974 ), and pulled up the 73 link and hit pickups. First picture I clicked on and used my magnifier tool I have on my computer ( ok, I am old I know ) and pulled this image at 250%. (It will not let me transfer the pic at 250%, it reverts back to normal, sorry).

Even in this image (without being 250%) it looks like a drip rail on the drivers side. Same with the 74 truck, am I seeing it wrong or something.
The 74, for some reason I can not post the pic of the 74 in the link here, and I can not get the magnified picture to take and transfer over to this website, but the 74 pictures look like drip rails also.