Changed the heater core in my Durango over the past 2 days.

Just curious, after you'd done that for a couple times, how long did it take you to do a evap or core? Also mitchell said I had to, but is it necessary to take the steering column out. After I got done it seemed like I could have lifted the dash over the column. And are there any special tricks to getting the heater box nuts off from behind the block?
did it in under 4 hours,mitchell/alldata changed labor times to same time as warrenty,used to just droped columb & cover it,never pulled dash all that way out,would roll & pull dash sideways from r/s.to get nuts on fire wall i had 3/8 drive ratchet about size of 1/4 ratchet.after closeing three dealer ships in five years in chicagoland area done.....after 16 years......been fork lift tech on the road for 3 years make more $$$$$ that ever:happy7: