The magnetic ones come with a cigarette lighter plug, but I cut that off and wired all of them to a trailer plug set that I had laying around. Again I take mine off for Summer and only use in the Winter so I want them easy to remove. I just leave the outlet wired and mounted all year around.
Hope that helps or at least gives you some ideas. The magnets are quite strong, but if you have a lot of trees or storage area height concerns, you may want them under the ROPS. I have hit tree branches and moved the lights, but never had one totally pop off.