Assuming the 2nd "C" is mis-read from an "S" (or E perhaps) - I'm stumped on the "3".
9 is indeed the year (which it must be as it precedes the Z), then the "3" is in the "model type" slot which is normally just 4 (pickup), 8 (blazer), or 6 (burb). 1 is the GVW (1/2 ton). But what's that there "3"...

Mystery to me. Chassis-cab?