> Also, I'd like to know the size wire I should use to connect the auxiliary

> battery positive to the starter battery battery.

I just recently did this conversion myself. Here's my setup:

- 8 gauge cable from main battery under the floor up through a 1/2" grommetted hole in the auxillary battery box

- connected to a 75amp battery relay purchased from a solar/alternative energy retailer

  (also available at RV stores)

- another 8 gauge cable from relay to positive terminal of an Optima 750 yellow top

- standard FLAPS 12" grounding strap to the negative of the Optima

- two 8 gauge cables from positive aux battery connection: one routed directly to stereo power amp (hidden behind the glove box) with 30amp inline fuse; another (also with 30amp inline fuse) directly to a "modern" fuse block that replaces the "dinky" Westfalia one behind the driver's seat. Refrigerator and all interior lights connected to this.

DIAGRAM:

                                           to ground

                                               \    _____________________

               fuse block                       \  |                     |

                    _      inline fuse           \_| negative            |

refrigerator1------|-|        ____                 |                     |

refrigerator2------|-|-------|____|--------|       |      Optima 750     |

interior lights----|-|                     |       |      aux battery    |

future             |_|                      \___   |                     |

                              ____              \  |                     |

stereo amp-------------------|____|--------------|-| positive            |

                                            ____/  |                     |

                                           /       |_____________________|

           Blue (to inst cluster)  ____    |

                                       \   |

                                       _|__|_

                                      |      | 75 amp relay

                                      |______| (replaces dinky standard relay)

                                        |  |

                                        |  |        _____________________

            Red/Black (to starter) ____/   |       |                     |

                                           |       |                     |

                                            \_____ | positive            |

                                                   |                     |

                                                   |                     |

                                                   |     SEARS Diehard   |

                                                   |     main battery    |

                                                   |                     |

                                                   |                     |

                                    to ground ---- | negative            |

                                                   |                     |

                                                   |_____________________|

Hope this helps...

Cheers,

<bold>Michael J. Sullivan

</bold><italic>Director of Catalog Design

Open Market, Inc.

</italic>

'87 GL Syncro Westfalia

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