You can get the transmission arms for the wipers at Classic parts or most any other parts place. RBs Obsolete parts has a good set of wiper arms and modern style blades. I got a set of them and they work a whole lot better that the original reproduction ones. Since you're not going original, the electric ones are the way to go. The unit bolts right in where the original went, easy as can be. But Rich is right. You have to relocate the switch. I put mine in the hole where the original ignition switch went. Used a 3/4" elecrical knockout seal with a hole drilled in the middle to hold the switch itself. The setup works great.

My truck: She may not be the prettiest girl at the dance, but she's all mine!