You are right BillRo. An alignment is critical, and critical to be done loaded for a trip, which the factory could never simulate. And the shop that can handle the task adequately are hard to find. My local shop does motor homes as one specialty, trucks and buses too. They have various specialty parts and also bushings on display to help explain things for customers. They go through various alignment scenarios, and how they adjust for such extremes that the chassis itself cannot be adjusted far enough without such special parts.
The shop told me to go on a weekend get-away, making sure we include everything we typically take along. When we get back home, leave everything inside, but be sure the gray and black tanks are empty, and the fresh water tank is full as that is the most common travel mode. Also fill the propane tank and main 55 gallon gas tank. He also said it wouldn't hurt to place heavy weights behind the driver and passenger seats to simute the two of us in those seats. His alignment is then done with that weight placement on the chassis and also considers a 1/4" road lean to the right curb which is the national standard for water run-off. It all made sense to me.