Leon and AdobeDave,

Very good points.

These are practices we use in Aviation as well. Not only does it help with power distribution it also lends itself to saving weight too. We do everything with weight, reliability, ease of maintenance and possibility of failure in mind.

Wire weight does add up quick.

On another note. Something I see in many vehicles that makes me cringe is Ignition Boxes mounted right next Data and Digital Boxes (EFI, Timers, Controllers, Delay Boxes etc.)

In aviation we go a little extreme and separate AC from DC from Digital / Data lines.

With that said it would be a good idea to keep any High Voltage systems or Boxes separated from Digital and Data boxes.

My own plan is to put my Ignition Box and relays under the dash (I have a removable dash) and mount my EFI and Controllers on a panel in the passenger area somewhere. Probably in the door like we see on Pro-Cars.