I have finally gotten around to measuring the stator output (no excuse, pure laziness).
First I did the resistance check from stator wire to engine ground - open circuit when both running and shut down, so no probs there.
Next I checked the AC voltage output while running (stator not connected to anything besides the meter):
1k rpm (idle): ~15V
3k: ~45V
5k: ~65V
So that all appears to be in order (phew!), and I just need to slap a decent RR on. Like I've previously said, I'll be going for the Shindengen unit from roadstercycles (he also supplies a mount adapter with the correct spacing for the standard RR mount holes). The kit he supplies will just require the two stator wires to be connected, so I think I'll use a pair of Deutsch pin contacts (no plug housing) and heatshrink them. The rest of the kit wires direct to the battery, replacing the stock wiring.
At some stage I'll see about tracing the stock wiring through and removing it from the loom, but that might end up with the whole loom apart.
On another note, I noticed what appears to be a wee bit of blue smoke puffing from the top cylinder's exhaust at idle & when revving
Oh well... as I keep telling myself as I find issues on this bike "It was an absolute bargain Jase, it's a forever bike, you can always rebuild it..."