Paralysis by analysis. LOL

I do a Ford starter relay and a CD relay in alt line. Both of those placed in close proximity to your battery. Run one wire forward off an appropriately rated cutoff switch to the mopar starter relay lug, fuse it if you like. Pretty straight forward.

Just don't hook up your old alternator charge line. That will bypass/defeat the master cut off by feeding power back to the original mopar starter relay.