Is is necessary to disconnect the battery cable when you add in the needed relays & fuses?

 

I didn't and I don't see a reason to.

 

I wondered about that too. I just went through the process of 7 pin conversion and the new relays in the power distribution box. The owners manual definitely says to disconnect the battery. There must be a reason for that? So I disconnected mine. No big deal other than resetting the radio station settings and going through the process to teach the computer to manage idle speed. that process is in the owners manual also.

 

Probably not necessary to disconnect the battery, but it's good "electrical" practice to go ahead and do it. That way, if you make a mistake or accidently touch a connection to something you shouldn't have there's no risk of blowing a fuse or damaging anything.

 

You hit the nail on the head. That is the reason they state to disconnect the battery. If you happen to touch a live wire to the frame somewhere (ground) you will blow a fuse.

If you do not wish to disconnect the battery then you can simple remove the fuse and/or reply for the circuit your working on and will have no problems.