Hello. Please bare with me as I am just getting started in robotics.
I have been trying to come up with a way to hang round driving lights on the front of my car but flip them around 180 degrees (backwards) for the times that I am not using them so as to keep them from getting broken or chipped. I would mount the lights on a common horizontal shaft that would need to rotate 180 degrees from backwards to forwards. I have found a great gearbox option by utilizing a common yard tool “roto-tiller attachment”–the kind that attaches to gas power heads. I can’t find any info on the gear ratio but if I attach my corded variable speed 1000 rpm drill to it and go at the fastest rpm, it takes several seconds for the shaft to turn around 180 degrees. It is small, STRONG, and waterproof so it can take being hung on the front of a car. It is a T shaped box where the power input comes in from the top by way of a square drive shaft inside of a metal tube. The driveshaft from the tube slots into a female fitting on the tiller gearbox. Motion is distributed to the axle which turns at a much slower rate. I have found that a programmable garage door opener has a 1/2 or 3/4 hp motor (overkill) and has programmable limit switches as well as a remote control. My question is this: could I just use a simple gearmotor, a geared stepper motor, or a stepper motor with encoder? Planetary geared stepper with encoder? Obviously I am a bit clueless…but I am determined. 
Any advice is appreciated. I know I need a stepper motor of some kind as well as a controller that can have two programmable presets for exactly how many revolutions to go before it stops. Then reverses with the other switch. Or ai need a servo that only goes 180 degrees. but then i have to figure out how to turn the shaft, so I figured a stepper was a better idea. Thoughts?
Thank you!
PS I am looking for something smaller than the garage door opener because of the amount of limited space I have. I also have to figure out how to use a flex shaft to get power from the remote mounted garage door unit to the top of the gearbox. Much easier if I could just go directly into the gearbox from directly above it.
I included a pic of a common tiller attachment.
