1968 GT 390 FASTBACK w/in dash A/C

I have this car and as you can see by my signature I have a galaxie too. Same motor but the galaxie has factory indash a/c I wanted retrofit it into my mustang. Can it be done? Has it been done? What do I need to do it? Please include some really in depth details. I realize for starters I'm going to need dash controls. Did they make 68's with indash a/c back then or am I going to have to use a newer years dash board controls? As far as ducting goes how does that work

68 Mustangs came with in dash a/c Galaxie stuff is too different. I would look for a doner car.

The galaxie is the doner car. Just for the motor and trans though. I don't want to mod the stock s-code motor from my mustang.

I think I wasn't specific enough. What I meant was I'm just going to use the a/c components on the engine from the galaxie. It was serviced in 2003 and pumps out cold in the galaxie now. I plan on making the mustang look stock with the dash board controls vents and ducting.