I bought an electric linear actuator off eBay a few years ago (operates like a hydraulic cylinder) Its labeled for 24v but runs easily on 12v (1/2 the "normal" speed). I think it would work for a snow plow blade because the time its generally used is for swinging the blade when you are not plowing, but changing lanes or direction. The important thing for plowing is its ability to stay put when you have it at the angle desired. My actuator would do that job.
When you apply power to it, it runs one way. Break the circuit and reconnect runs it the other way. So, a push button works to get the desired length (position). This may have been a gate opener design at one time. I've used it to raise the header on my hay baler when I didn't have any rear remotes...