Alliance Coach is physically where the Monaco Florida Service Center used to be, in Wildwood, FL (south of Ocala). It is no longer associated with Monaco, though. I haven't been there myself, but haven't heard any negative reports yet.
For the type of work you want done, I would go to a engine/chassis place rather than an RV shop. Cummins Southeast in Ocala is a good shop and they are a Cummins Coach Care facility.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL