In older boats the wiring often requires upgrading to meet current safety and materials standards. New wiring is available and can be used to meet the visual aesthetic of the period of an older boat.
Older 6 VDC systems can be converted to modern 12 VDC.
It is important to maintain older instruments and gauges in working order. They can be rebuilt and repaired in a keeping with the appearance and authenticity of an older boat. A choice can be made to mechanically rebuild, reface, or re-plate as needed.