Tow Me
+1y
73-80 have round headlights. Front fenders and hood are not sloped like the 81-87 C10s. Lots of minor differences...different dashes, door panels and so on.
1980 C10 are uglier than shit. They tried a square headlight with the 73-80 frontend.
81-87 are all similar. Changed to square headlights and bumpers changed. Cabs look the same but the hoods mount differently (compared to 73-80). Bedsides are similar except gas door was added. Tailgates changed slightly but still bolt up. Only real changes in the front between the years were 2 and 4 headlights, grills and trim.
Suburbans and K5 Blazers went until 91. These parts can be used on most of the years below. They offered much better interior pieces too. The front ends are the most desireable. Headlights look more like 88-98 Chevy C1500 Bumper have impact strips on them too.
Hope that helps some.