Welcome, don't know if I can give sound advice but I can certainly give an opinion.
Our buses are quite different. There is a bus guru in Avon, he travels all over the US repairing buses. He won't touch anything as new as yours though. He specializes in Detroit 2 strokes. If you're ever up this way give me a shout. You can text me at 260-two two 4-43 two 0. email is somewhereinusa-at-earthlink-dot-net. If you do contact me put skoolie in subject or I'll probably dump it without looking at it.
Dick