Existing pick list in soft phone layout

U.S. based company. We buy, sell, and fix firetrucks. We'd like to be able to use an existing pick list in SalesForce in our soft phone layout. We currently have a pick list under Activity History where we select what kind of contact it is and whether it was inbound or outbound. We run reports based on that. We want to continue to use that method and would like to have that picklist show up on the soft phone layout. We currently has 28 users that would use that function.