I recently put an 86 Ninja regulator/rectifier on my Z1. 30 bucks at the scrapyard. Got some advice from Loudhvx (our electrical guru). It wasn't too hard and it works great, but I don't know if your bike has the same kind of alternator etc.
I used the original green plug off my old rectifier and wired the regulator/rectifier combo to that, so I just plug it into the green recepticle.
New reg/rec
(connect to)
> Old wiring
3 yellow wires
> yellow,pink,blue (green plug)
brown
> brown (green plug)
black
> battery neg (-)
white/red (live)
> where white wire on old rectifier went
The original green plug also had a black/yellow ground wire, capped that off.
Loudhvx recommended I wire a 15V inline fuse into the brown wire to protect the circuits while testing, which I did. I took it out a couple of weeks ago because it works great.
good luck
dutchz