Tristan, do you have a sound system, electric fan or other electronics on that car? Because I have too many wires on the positive terminal of the battery. I want to find a way to eliminate all that clutter. Anyone?
Auto electrical systems are supplied and fused through a fuse box and fusible Link Boxes, not additional wires running across the engine bay to the battery. If your fuse box is full, get an additional one.
A very clean install is to keep a distribution block with enough legs for the heavy items:
D)To Fusible Link->Fuse Box
E)Aux (extra connection)
Your fans, radio, etc. need will then draw power from the fusible link terminal off your dist. block and then fused at the recommended amperage.
You can purchase these, but I have made one from a piece of 1/4" copper, drilled and tapped for distribution, and attached to a 1/2" piece of micarta. Use no less than 4 awg for the runs, and ground your engine block to the chassis (like a shock tower) with 4 awg. Your starter and alternator will thank you.
Most of our older cars don't have fusible link boxes under the hood, but any 80's and newer car in the junkyard should have them. Snag one and run the important stuff directly to this box; ignition, fans, fuel pump, etc. and use the Main to feed the cabin fuse panel, route these wires directly into/along the harness and it will look very factory. At the junk yard make sure to snag the line feeding the box as well as any connections leaving the terminals, that way you can de-pin and re-solder any terminals.
I'll try to get some pics of my distribution block when I get home.edit: I change my recommendations from 2 to 4 awg for the short runs and engine ground. Although I would suggest 2 awg for a rear located battery.