I would not guarantee that the RE60 would work in it, they are very similar in principle but when we have overhauled alt we just use the indentical replacement reg... makes sense and then can be assured there wont be a problem there. Those regs are still available, but u may have to try an auto electrical supplier.
Now... i'll try to simplify everything for a sec. When testing an alt on the bench, the only things hooked up to get it to work are:
1. Warning Light: More than likely that push on terminal on the old loom to 'L' terminal on reg (can be checked as mentioned in previos post)
2. The big B+ to the back stud/bolt on alt.... ie. the ring terminal in that loom
3. The earth: not needed when u put it on the car, as alt is grounded through the block etc
4. Sense: Use another eyelet terminal off the B+ and connect to the other pin in reg, 'S'
That is all i needs to run and charge like normal, the D+ and D- terminals are not needed as they are connected through the plug on the reg.
As for beefing up the B+.... depending on what output that alt can produce, i'd definately recommend it as that existing loom doesnt look like it would handle much more than 40 Amps. It doesnt matter if u go from the battery or the starter, as the main cable from battery to starter is thicker anyway.