Get the factory parts from a wrecked S10. I know a guy that had a whole setup for your truck for I think 250 or so. Brackets and all. He is on the list. His username is Pixelmonkey. Tell him Proflo'd told you about it.
It's work but if you REALLY want AC I would say it is worth it. If you already have the vents in your dash it will be a breeze. If you have a truck like the Wildside and it has no vents in the dash, you can either have the AC come out the floor and defrost or replace the dash and all the ductwork.
i'm gonna get to this point some day. i got another dash mainly for this reason. while it is out i'm gonna customize. i've already stripped it and i'm cutting the top back for some fiberglass work. i want to cover the bottom in suede. i got the dash and most of the AC plumbing for $75. i thought it was a decent deal.