http://home.earthlink.net/~gamba2/images/macIIcisch.GIF is worth a look if you have not already seen it. Before any cap surgery you can measure if +5 continuous is coming from the infamous power supply zener diode Z1 and if the startup circuit depicted on the motherboard is commanding the power supply to start up. Caps C6, 12 and 13 of course have to be good, and additionally any cap leaking could cause faulty connections not shown or intended. The PS is tedious to disassemble but if need be the +5 continuous "TRKL" schematic is easy to manually reverse engineer working back from the connector green wire to pin 10.