To my knowledge , starting in the early 1970`s - late 1980 , "c-10" represented 2 wheel drive and k-10 meant 4- wheel drive .

But earlier today I saw a video of a 1983 K-10 silverado , I thought the "C-10 silverado customs " were supposedly made 2- wheel drive .

Would this be a custom ?

Anyway , If possible I would like further knowledge on the meaning of the "C" and "K"