You want a good wire crimping tool for electrical spades.  Not expensive and you will use it a lot.

 

Get Red and Black shrink wrap in many sizes.  Replace the old shrink-wrap everywhere.

 

Don't skimp on electrical tape, buy 3M.  I also used liquid tape paint and put that under shrink-wrap that needed to be stronger or that might be exposed to moisture.  I used very little electrical tape.

 

You need a digital multimeter (DMM).  The ones that have an audible tone for continuity are preferred because the wire can be verified quickly for continuity without needing to look at the DMM.

 

LED bulbs lower the load on the old wires (Alternator light must not be LED and it must draw current).

 

The 914 round relays have pins that should be cleaned and use a razor blade to open up the X cut in those pins.  Polish the pin holes with 320 or a diamond file.  Keep a few spares and use the headlight relays from the front trunk area in a pinch.