Setting up an Andersen WDH

You don't need your truck to be level. You just need the front returned to near it's original height. The ford manual will tell you exactly where you need to be. The TT needs to be level or if you're not on perfectly level ground, parallel. You need to measure from the ground up to the frame on the TT. Don't use a level unless the ground is level.
With your HD Ford you shouldn't be having the wobble issue. The problem with that TT is everything heavy will be in the rear of it. It already has a marginal TW. I'm thinking you're tongue is too light.