That is what I did in my 273 small-block. Look at a Magnum engine and you'll see that is what the Chrysler engineers did from ALT+ to BAT+, running right across the timing cover. Indeed, I used the cable from a Magnum V-8. I don't directly attach to BAT+, but rather to a new fuse/relay box beside the battery (can see in my avatar).
In a slant, running ALT+ to the starter relay is the easiest path. No, need to add another wire from there to BAT+ since there is already such a factory wire.
I lost you on the need to connect two 10 awg wires to the fusible link. A photo would help. We assume that is the cabin feed, via the bulkhead connector. What loads would you have in the cabin that require such massive current? If you did draw such current, it would melt the bulkhead terminal which is the problem the MAD Bypass is intended to fix. If you do need such cabin current, do the "fleet bypass", as the factory did for loads like a police spotlight.
