Distribution panel fasteners
Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models
The original fasteners that secured the fuse block to the headlight bucket are 3 mm × 0.5 mm × 8 mm. Were I to need replacements, I would likely select McMaster-Carr part number 92467A119. I would combine this screw with a lock washer, McMaster-Carr part number 91111A121. This washer is intended for use with 4 mm screws. But Moto Guzzi originally used this size lock washer and it seems to work well with the truss head screw.
Charlie Mullendore of Antietam Classic Cycle provided me with some additional details. In Charlie's own words:
It's *close* to 3 mm (3.07 mm I measured) and *close* to 0.6 mm pitch, but my thread gauge didn't drop into the threads perfectly. It measures exactly 0.12 inch though and 40 TPI though. Almost seems like a 5-40 screw. I'd call those slottedtruss headsdue to the wider head. Split locks on those too. 8 mm or 5⁄16 inch length.