Subaru heater help!

anybody have any idea how hard it is to get to the flap that controls the heat into the car on a 2003 Subaru Impreza Outback Sport? The dial that takes you from cold to hot started to get hard to turn a few weeks ago, then the connection obviously let go when it was in the hottest position (flap full open), so that now it’s all heat all the time. i’m picturing having to take the dashboard apart, but maybe it’s not that difficult?

Check this, if right, it maybe an easy fix through the footwell. We will pray for you.