Start with the whole business, not the channel.
A map drawn for a national manufacturer with a long purchase cycle, a dealer network and a community of owners. The whole market on the outside, paid media inside it, owned and borrowed audiences inside that, earned attention inside that, and the sale at the center. Every ring carries a target for what the plan should add. Nothing that moves the sale is left in another room.
Illustrative. Drawn from a plan for a national manufacturer with a dealer network.