[Maurice Johnson]

Ahhhhhhhhh!!! - dedicated grounds--music to an electricians ears. My 2 cents added in would be don't be tempted to take ancillary grounds, (switching relays, slave solenoid,etc) to the engine block with its dedicated neg return to battery. Different electrical potentials can all add to galvanic action, often confused with electrolosys, especially on motors with mixed components. Aluminum heads on iron blocks for example. BIG problem out here in the marine world.