I have never had the the privilege of seeing traffic lights built or installed, but seems the just come already built ready to install.
In the above picture you can see that the people at the traffic light factory just threw it on a flatbed truck and sent it on its way. All you have to do is prop it up and plug it in.
This ia a more expensive model we talked about earlier this week. The truck just simply pulls up to the intersection where the light goes and it plugs right in. No lifting required.
I asked Big TruckerB about these delivery methods and if he had ever transported a traffic light before. Well, just like finding out there was no stork, he told told me these drivers are just morons who removed the lights by hitting them, not installed them. Bummer.