99 gmc savana a/c installation on a truck with an a/c delete from factory

[duff007]

hi, im trying to put an ac in my 99 gmc savana. it was deleted from the factory(not my choice lol, brought it used). it was the first truck i ever brought and started my business with. i have 6 more in the fleet now but its still preferred by me and my guys over the 2018 and 2020 savanas for towing and going off rd or driving in heavy snow. so i wanna keep it and just did a big overhaul on it, but the ac is perplexing because some of the wiring is there, as is the bracket for the compressor etc. the GM dealer says theres only one wiring harness, whether the trucks came with ac or not and they probably just tired the wires off somewhere. which is true for some wiring but i cant see any wires that would be for the main fuse box above the pcm, tied off anywhere. any guidance on what they did at the factory or where the wiring would be located, would be so appreciated. or if anyone has done this before and knows a work around for certain wiring, im all ears. i have all the oem parts including the dashboard controls with the ac setting, its just the wiring thats holding us up on this. thank you