I just replaced all 4 terminals with eyelets. My cables are a #6 so I found #6 crimp eyelet ends, they can be insulated or w/o but the ones I found at hardware store on had a 1/4" hole, battery is 5/16". Got my drill and took care of that issue. I have a pair of Klein lineman pilers that will crimp the connection if you use it w/o insulation. Then I used heat shrink tubing and maintained the terminal covers for safety. The disconnects are also available thru Grainger, they are the small version of what is commonly used on lift truck battery connections, select by wire size and I think crimping required. I've considered them also. The square lug I think is a lug used in house wiring.
2005 Dodge Ram 2500 5.9L 6 Speed
16" Michelins, Hi Spec Wheels, Max Brake, Carslile Actuator, Equal-i-zer, Dill TPMS. Campfire cook.