Howdy! I am trying to remove the defroster fan from a 71 MB 280 SE sedan. I have taken almost everything out from under the dash with the exception of brake and accelerator pedals, and air conditioner condensing unit. The fan appears to be in a unit larger than any access area behind the dash. It is loose but when I try to slide it to the left, the right pipe of the heater core gets bound with the firewall above. When I slide it to the right I run into the airconditioning unit. Do I have to take out the air conditioning unit in order to remove the assembly containing the fan and heater core? thanx. sb.