Blend door actuator replacement HELP

Hello, All. I'm trying to replace the blend door actuator on my '03 Envoy. The problem appears to be unit failure - the new one moves when it's plugged in and mid vent position is selected. How much of the dash has to be dismantled to access it. The three screws that secure it are out but there's an immovable steel support blocking removal. Can anyone recommend a schematic or manual? Can't believe there wasn't a better way to engineer the accessibility for this given their propensity for failure.
Thanks.
Doug

Do a site and/or google search, I believe there is an update that is simpler to do.