RADLOK Pass-Through Bulkhead Bundle

These pass-through  bulkheads are the best option when trying to get power or ground cables through the firewall and keeping everything weatherproof. These have also been used to get cables for trunk relocated batteries into the vehicle cabin. 

Most people that use these typically use 3 sets:

 1 Red Set for alternator

1 Red Set for starter

1 Black Set for chassis ground