hi, my name is jas on and i will be assisting you today.
the blower motor on your unit has to be removed from the side. you have to pull the right cast side and disconnect the white and blue wires. if there is a wing nut be sure to remove this also. after removed a magnet holds the motor in place. tilt the blower up and pull out.
to get the actual unit out, you will need to remove the panel set and flue connection if you do not have adequate clearance.
here is the address link to the owners manual that can provide you with specific detail.