Before ordering the new switch, I verified that my old switch was actually broken by testing its continuity when the lid was closed. The switch stayed open even with the lid closed. I even disassembled it and tried cleaning and lubricating it with contact cleaner, but that didn't fix it. The design is surprisingly fragile (more like a thermostat than what I would have expected as an interlock) and it had apparently just fatigued and lost spring tension over time. Ordered new switch which arrived very quickly. Installed the new switch and verified that it DID have continuity when the lid was closed. It works perfectly!