I think you can leave the switch in place, pop the rocker off and get to the guts. Use tweezers to lift the parts and dirt out and wipe cavity and contacts clean with tweezers and cloth dipped in solvent, lube and re-assemble.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked