You will have to pull rear seat to remove the rear defroster wires.
We didn't pull the A pillars off. I do recommend using MB or simular sealer between the glass and the rubber. I didn't and my still leaked till and good bead was put between the glass and rubber.

__________________
1980 300SD Manganese Brown Metallic Clearcoat 248k
1979 300SD White 148 k
1984 300D Silver project car for daughter
1982 300D wrecked
1980 300SD 310K not running