I've done turkeys on my Eggs, Weber Kettle and pellet grill and have never had an issue with the dark meat finishing before the white meat. Do you have the water pan in the WSM as a heat diffuser?
"Ron Rico, Boss. You can call me Captain Ron..."
The Naked Fatty!
FEC-100/BWS Party/Memphis Pro SS/PBC/LBGE X 2/SBGE/Mini BGE/Nomad Pellet-matic/Good-One Model 42/WSM X 2/Cookshack Smokette 008/Weber Performer/Saber Cast 500/Weber Gasser (RIP)/Weber Kettle X 2/Weber Smokey Joe/WGA/UDS/Coffee Roasting Gasser and a pickle
Remembering a friend