Remember when they introduced being able to slide things up and down walls in sims 2? Well I thought since a lot of the code is copied from both sims 2 and 3, (for example the social interactions have got to be from 2, because you can do the same thing over and over without the other sims getting offended) that perhaps that would be in there too. Well, it is! That explains how they got the lights up so high! You use the ' and / keys to go up and down respectively, and the [ and ] to move things left and right without snapping to grid!
It might be one of those completely obvious things to other people, but I hadn't bothered reading my game controls, since I've been simming for so long.