Very good, Andrew. Glad you found what you did. Just in case you wind up exploring further, I've attached two files. One is the schematic from Monaco that covers the turn signals, and the other is one that I made for my own use that covers the brake lights, part of which feeds into the turn signals circuit. Our '06 Dynasty shares a great deal of the electrical design with the Sig.
Enjoy that coach. You've got an awesome one!
Jim & Angie, Boise, ID
2006 Monaco Dynasty Countess III
2017 GMC Acadia Denali