C/K Models
"C" denoted a two-wheel drive; "K" denoted four-wheel drive. Often people refer to EVERY Chevy truck as a C10 even if it has a 4WD. The letter is the 5th digit of your VIN.
For Squarebody's 1987-91, Chevy changed the C to an R, and the K to a V as they were being produced alongside the next generation of GM trucks. G10/20/30 Vans are 2WD and 4WD and can use the same LS conversion mounts from the same year C/K equivalent.
Specific Swap Information By Year:
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