If that coach were to ever start to slide, those level legs are toast. Obviously a gas coach can't lower down on the bags like a diesel coach can so I can't criticize these folks. But, I think I would level manually if that is what I would end up with.
Leave the rear wheels alone and just lower the front jacks until they touch and maybe an inch more. The rear wheel parking brake will not hold unless firmly planted and this guys rear wheels look like you could slide feather underneath them.
Hope he doesn't fall off the blocks.
MM.
It's his coach