It will have severe bump steer to the point of being dangerous. Even if you use very stiff springs to cut down on axle vertical movement it will turn even though you hold the steering wheel in one position. The mid 80's Toyota 4wd power box is a small unit that can be mounted where your factory box is and works well. A search will show many posts on this. Flaming River is making an electric power column now that adds nothing inside the engine bay, it's under the dash and not bulky at all---about the size of a power window motor. Malibu's started using electric in 2005 so salvage units should be possible to find. No hoses, belts, pumps, linkage, and U-joints. If your old box isn't worn out the shaft from the electric unit could be grafted to it much easier that converting to a front of the axle set up.

Evan