>Could you possibly post a few more details as to exactly where you
installed the
 >capacitor and ground cable?

Da Cable:

One end of the ground cable goes to the alternator body.
I used one of the four small (4mm?) studs that holds the
alt together. I think I used a cable lug with a #10 hole.
I found a nut in my metric junk hardware box that fit the stud...

The other end of the cable I bolted to the body sheet metal..
I found a hole, aprox 1/4" diameter in the body metal roughly
near center, above the bell housing. I used the dremel tool to
clean a small patch of paint from around the hole and bolted
the cable there with a 1/4" bolt and nut.

Da Capacitor:

One end goes to alternator ground. Use another one of the
small bolts that protrudes from the back of the alt.
The other end of the capacitor goes to the LARGE (output)
terminal on the alt. You'll need about a wire lug with
about a  5/16" hole.

>any suitable grounding points near the engine. Any detail on where you located
>things would be helpful - my changes have had NO effect so far.

Well, it's very possible that it won't help in your case...
There's probably a lot of reasons for VS or VS related
symptoms, and what cures one may not cure all.

I'm quite sure it cured mine, and from the things I witnessed
on the oscilloscope, I can certainly see why it helped in my case.
It's certainly a relatively cheap and easy thing to try, so it's
a good starting point in either case, before resorting to more
expensive attempts...

Good luck!
Steve