30BR,
Be careful, Dometic may not have tried it on a rubber roof. The roof isn't their concern, only cleaning the coils, and their profit margin. Also most commercial coil cleaners are weak acid based, so try not to inhale.
Removing 4 bolts and 1 or 2 plug type connectors is all that's required to remove the AC (on most). Put it on the ground and you can clean everything without worry for the roof.
It's around 70 or 80 lbs. I've removed them by myself using a rope, a couple of 2x4's or plywood leaning against the side, and sliding it down. It's harder to get it back up. I'm a little older now so I wait and get someone to help me.
Good luck.