Using AnimMontage Member of Owning Character in Anim BP?

Is there any way to convert an AnimMontage instance to a Pose Link Structure? I’m working on an FPS and our modeler has made the FPS arms and weapons in to separate models. Now, in the blueprints for each weapon, we’ve specified what animation the FPS arms should use for that particular weapon. Then, in the Animation Blueprint for the FPS Arms model, I want to get the Idle animation from the current weapon that the player is holding and use that as the input source for the “Final Animation Pose”. I have no problem getting a reference to the current weapon’s specified idle animation, but I can’t find a way to convert it so that I can use it as a pose. How can I accomplish this?

I do not want to go the way that the Shooter Game did and do a bunch of casts to see what kind of weapon they are holding.