Re 59 Thunderbolt: While the body, frame, and suspension are custom, the engine and transmission appear to be standard Triumph TR3 1959 vintage. The original TR3 had positive ground electrical systems but were easily converted to negative ground, which is probably why you saw positive voltage on the ground connection when wiring the dashboard.
Re 59 Thunderbolt: While the body, frame, and suspension are custom, the engine and transmission appear to be standard Triumph TR3 1959 vintage. The original TR3 had positive ground electrical systems but were easily converted to negative ground, which is probably why you saw positive voltage on the ground connection when wiring the dashboard.