I bought a power window motor from the junk yard for $25. The motor has a gear that connected to the gearing on the window. I found that a socket (I think 7/8") fit it perfectly. I then cut the tube used for the crank and the inside diameter fit the outside of a 9/16" cracked socket I had. Then I cut a 3/8" square stock about 1 inch or so long to connect the two.
Then I fabbed up a little mount for the motor and wired it to a DPDT (Double pull/double throw) switch. I put an inline 10 amp fuse. Works like a charm.
The switch is an ON - OFF - ON with a spring that makes it go back to off when you let go of the switch. Pull it one way to go right, the other way to go left and let go of the switch and the chute motor stays off. Someone here helped me identify the type of switch I needed and told me how to wire it.
If you go this route, post back and one of us can tell you all about the switch required.
Here's some pics.