Should there be a little "play" in the swing gate to the extent that it rattles when driving even over small bumps. It is rattling at the latch because of a small space between the stopping point and the gate itself. Also some of the parts are rusting because of all the rain here in Florida (i.e. the stud for the latch handle and the castle nut on the bottom). Anyone experienced this or just me?

Do you have a delron block that the gate rests on where the latch is? You should.

Yeah, but i am just picky about sounds and knocks. I have since but some soft pads there to keep the noise down.

I still wonder if I need to buy more hardware to replace the rusty ones. They kinda tend to leave stains as they run. I am not sure if rust spreads in areas other than what you see. Some of the spots that got dinged up in shipping show a little rust but I don't know if it will go any further than than.

I replaced my hardware with stainless steels bolts too. I didn't like the rust either!
I also made some brass bushings to replace the delrin ones and the steel sleeve in the pivot. I also made another spring to go inside the latch spring. I have had the latch pop and the Arm swing out on the trail when I was twisting the truck pretty good. The spring is tougher to pull up now, but will stay locked in place on the trail!

I have a noticable rattle particularly off-road, I also have a little bit of sag which requires me to lift it slightly when closing the gate. Also my gate is not straight up and down, it leans back slightly, and my offset wheel puts the tire about 3 inches back from the vertical bar.

Normal!