[A bones]

We mostly do not testify about Datsun equipment.

Myself I would gamble on 12 volt. Datsun hadn't run 6 volt for decades. If it smokes, how difficult would it be to replace the parts with 12 volts.

Perhaps, if you want to be cautious, locate an auto recycler or an electric motor rebuilder. Pictures probably would work, if not bring them the equipment to be certain. Best of luck