Fire guy

Thinking it's your cruise control cut out sensor.   It will only leak air when you push on the pedal.   It kills the cc when you touch the brake pedal, pretty cheap part but if your cruise still works and shuts off when you touch the brake then it's probably just leaking at the threads which is either just loose or the manifold is cracked.  Just make sure you get the right switch to replace.   They all look the same but some are normally open and some are normally closed.   Good luck

I have a 99 century,  changed several of those switches before i figured out it was actually the manifold that was leaking so changed the whole thing out.   Anyway,  the attached diagram helped me figure things out.   Not sure if it will cover the 04' but worth a look.  I think i just used some small channel locks and i removed the one below it first.   Good luck!

Pretty sure it was camping world.   You pick the parts and build what you want.   We obviously went with the middle seat and console but could have just put an armrest or a skinny seat in as well in the middle.   A little on the pricey side but we figured if it didn't work well or we ever sell the truck,  we will move it to the 5th wheel and get rid of the crappy rv couch/hid-a-bed.  I really need some windows though like jenandjon did. 

Bought some aftermarket lap belts that bolt down through the floor and backed them up with some plates underneath the cab. 

We gutted the sleeper on our Century and put in this rv couch.   Tight fit but it fits.   Comes in 6 pcs so it wasn't to hard to get in the doors.  Wife works from there when on the road so i needed her to be comfortable. 

Now i know what to look for.   Thanks for the info. 

That's good to know.   The more i thought about it after i posted that pick i began to think that the framework that is there looked more like it would fit the sleeper doors and was a bit too big for just the windows. 

Worked that time.

 I have a 99 Century and when i stripped the condo sleeper,  the framework for the window was there.   Had a good pic for you but tried to put in a second pic and now i can't get either pic to show up!  Anyway,  should be easy if they are freightliner windows.   It's on my to do list for the winter to, just don't have the windows yet..