Some photos in this post. http://www.forabodiesonly.com/mopar/showthread.php?t=176755&highlight=Modernized+Engine+Wiring
No need to go whole hog and install a relay box like I did. I bought the PVC tubing on ebay. I knew about if from having spec'ed it years ago for an industrial product design. Easiest if you run wires thru before terminating. I pulled my existing front lights wires thru w/ the 57 terminals already on, which was difficult.
I saw a picture of a aftermarket fuse holder you installed in your car. Was curious as to where you bought that and how the install was done. Wondering if you extended the harness to reposition the fuse block or if it came prewired. I am contemplating replacing the old fuseblock with something newer in my 67 dodge Dart. Any guidance or suggestions would be appreciated.