I used a 1-wire GM alternator, sold at NAPA ($85 - a generic GM alternator for hot-rods, since it is modified to be 1-wire design), on the '83 FJ60 engine that I put in my FJ45. I ran the '1 wire' through the ammeter and then back to the new harness. Very trick and nice. I don't recall any bolting up issues when I mounted it. It's self-exciting and internally regulated so it solved a host of wiring issues for me. The family of alternators was mid-80s-mid 90s. I'm pretty sure I used the OEM bracket and might have had to space it one way or the other a bit. I used the pulley that came on the alternator.
Colo Springs, CO
'78 FJ40, '89 FJ62, '98 4Runner