Wiring up a 200 amp solenoid help?

I've bought a 200 amp continuous solenoid so I can hook up my kc lights to one switch and I've been trying to figure out how to wire it all up. It's a four post solenoid. I kinda figured that the two big post was for one connection going from the battery source on the + side and the other side running to the fuse box where I have the kc lights wired up to. Then I thought I could run a + line from the battery to the switch then to one of the small posts on the solenoid... no luck on the lights running with that set up. I was wondering where am I going wrong at? Do I have to ground the body of the solenoid to the chis or use the other small post as a ground? Any help will be great... Thanks ya'all.