I can tell you it is a bit of a job . Dash needs to come out . You do NOT have to discharge the AC . A few bolts are a booger . I can do one in about 3-4 hours .A few tricks , but doable for a DIY guy .
While your in there make sure to replace the Blend Door Assembly if it hasn't failed or been replace already. It will most likely break and you'll have to pull the whole dash out again. I agree, those engineers need a good can of whoop ***!
I wonder if they've made it any easier in the preceding models up to this date? That way someone could just open a panel 'under' the dash without removing it and simply replace all the HVAC parts needed in less than an hour. Why don't they ever consider the mechanic when designing these vehicles?
Remember to bag and tag every nut and bolt! It will save you a lot of grief and make sure everything gets put back on in it's proper place with no extra fasteners and rattles later on. It's well worth the time!