First what brand and model equalizer hitch are you using?
Next, from the photo, you look nose high on the trailer and the truck appears to squat a bit in the back. Both should be level.
On level and flat ground, unhitch the trailer and with no tailer weight on the truck, measure the height of the fender or wheel wells to the ground on all four corners and note the height.
Measure the height from the ground to the top of the hitch ball. With the trailer setting level, measure the height of the top of the tongue to the ground.
Set the hitch height on the truck so that it is about 1" higher than the level trailer.
Now hook up the truck and trailer and remeasure the fender heights and note them. The truck should squat about the same amount on the front and the rear. If the rear is low, you need more tension on the weight distribution bars. If the front is lower, less tension on the bars.
You can go on line and down load the manual fro the particular hitch and make the adjustment yourslf rather than trust the idiots at the RV shop.
A normal set up, it is better to have the front of the trailer a bit low, but not much.
By measuring the fender height you are cehcking to see that you are transfering some of the tongue weight onto the front axle of the truck.
It looks like you are pretty close on the set up, just needs some fine tuning.
As for using OD, read the owners manual for your truck and see what it says.
Good luck on the rig.
Be sure and visit one of the Texas Boomer rallies. This weekend we will be between Bellville and Sealy, TX