Installing a/c help!

Alright so I have a sears evaporating/blower unit that I got when I had bought my 75 dart sport. I also have a condesor that is currently mounted to my rad that I plan on using for the whole a/c setup. What do i need in order to cinver my car to a/c? are there any electric compressors I could use instead or maybe one that is not mounted right on top of th motor? Any help is appreciated thanks Dom