A/C available from the factory on big trucks?

[rkn463]

A while back someone here scanned in and posted some old sales literature for the 67-72 medium duty trucks and it showed available a/c but it was an under dash unit that looks identical to one that came out of my buddies 71 c10, and that one was a dealer added option (they bought their truck new).

With that in mind I know it is possible and I need to figure out where to mount the condenser because I do plan on adding a/c to my 68 c50.

-Richard