weight distr. setup/problem

[badstang79]

Hoping I can find some help here,
I have a 28' bunkhouse, dry weight is some where around 7360 lbs. on it with a tongue weight of about 800 lbs. I did some measuring after reading about proper setup on my hitch, unloaded the back sits at 40.25" and the front at 39.75". Without the bars and trailer on it's at 37" in back and 40.5" in front. When I put the bars on it only comes up a quarter inch in back and stays the same on the front. I went and had the dealership that set it up redo it, but the only thing that changed is the number of links. The trailer is level with the bars on. What adjustments can I make to level out the truck a bit if any?

Also I had long tubes put on with a sido magnaflow system, and compared to my factory manifolds and cherry bomb, seems like it takes a lot more grunt to pull it. Have tunes on the way. Will these help?