Manual to Auto trans

[BigRed63]

On my "new" 63 C10 I have a 250 inline 6 with a Muncie sm420 and a rear axle from an 84 Silverado(3.73 ratio) I was wondering what kind of cost am I looking at for changing to an automatic, probably keeping with a floor shift. We have a lot of hills in my area(especially at lights) and I'm wanting to drive it as my everyday, it's mostly for convenience. I know a lot of people here are the diy kind of guys, and I try when it is within my ability, but a transmission conversion is well beyond my skill set. I'm trying to get a ballpark figure that I need to save up for. Thanks