I used a semi flat rust oleum paint and just went at it. since the joints are sealed, I think no problem. I kept away from the boots of the joints but did the rest of the hardware.
Also painted my driveshaft, rear axle, brake drums (you don't have) , and the weld areas of the exhaust pipe. any place you might think it will rust, paint it.
I also got 4 cans of the rubberized undercoating and did the whole underside from cab to tailgate. Take down the spare to get the whole area above the tire. do this as soon as you get your truck since it will be very clean then.
Hope this helps,
Eric