My experience with using a breaker to replace a fusible link on my XJ left me stranded on more than one occasion. I upgraded my battery cables to 4 gauge welding cable, and installed a higher output alternator at the same time. My alternator was rated at 144 amps, and I used a 140 amp breaker. I had no indication in the cab when it would trip, and the rare time that it did trip it would run fine until I had no juice left in the battery. I have since switched it out for a 150 amp ANL fuse and had no problems.