I know of these things only because BTDT! I've screwed up every thing that can be screwed up on my bus...and fixed most of the screwups. Luke, Gump and Butch Williams (and a lot of other busnuts!) offered 'taylored' help when I was having issues. I'm only returning the favor.
Owning a bus is a full-time learning curve...a long curve may I suggest!

John benefits from our 87 NJT MC9 knowledge base. I don't know Bo about any other bus model. However, the repairability of an MC9/DDEC1 is remarkable...as long as one knows what to do. Easy coach to repair. Comparatively speaking.

John, glad the bus is running!
JR