2004 Pontiac Montana I am trying to install a knife type isolator switch and am unable to access the negative battery cable. Does the fuse box have to be removed to do this?
Yes, you do. You will also need to remove that steel bar (if you need to take the battery out or need better access). Do be careful while wrenching the positive terminal off, the water pump is very close (I shorted out the battery with my ratchet one time while removing the battery from my 2003 Montana).