Big 3 is really Big 2 in VW ????

[johnecon2001 5,000+ posts]

If the alt is grounded to engine block and the current makes the loop back to the batt as it is now, why would I need to run another wire from block to chasis? Wouldn't the connection that is in place now work just as well (isn't it currently made through the bolts that mount it?)?

just do the big three and not the big two. The third wire is there for a reason.