The webpage I was looking for was:

http://volksweb.relitech.com/90alt.htm

The text (for the archives) is:

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Alternator Alternatives

Last week, the dashboard warning light (AKA - "idiot light") for the
alternator lit up. When that light is on, it means that battery
voltage is higher than the alternator output voltage. In other words,
the alternator output is low or non-existent. I suspected the voltage
regulator mounted on the back of the alternator was the culprit, so I
priced one out from my local FLAPS. For $60 I could get a Bosch unit,
or $30 bought me a Taiwan no-name regulator. A Bosch brand rebuilt
alternator (Model AL27X) with a lifetime warranty from the same FLAPS
was $160.

Being the cost-conscious type that I am, I wondered about a used
alternator. Nice concept, but finding a donor Vanagon in the junkyard
is a bit rare around here. But the wreckers have plenty of late model
Golfs and Jettas, and the 90 Amp alternators from them will fit the
Vanagon just dandy! This is also a great method of upgrading from the
65 Amp alternator found in some earlier water-cooled Vanagons.

From these pictures, you can see that the Vanagon alternator (on the
left) is identical to the Golf alternator (on the right) with the
exception of the drive pulley for the alternator belt.

To use the Golf alternator on the Vanagon, simply swap the pulleys
from one to the other. The nut holding the pulley on was pretty tight,
so I had to use a hand impact driver tool to remove it. In this
picture, you can see both alternators with the drive pulleys removed -
exactly identical.

Here's the Golf alternator with the Vanagon pulley installed. Be sure
to re-use all the spacer washers exactly as before, and apply
Loctite(r) the threads of of the shaft before installing the nut. I
installed the used alternator, and checked the output voltage. 14
Volts, just as it should be!

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Unfortunately I am still without a part number or model year for golf / jetta

Chris

On 6/20/07, Christopher Gronski <gronski@gmail.com> wrote:
> Hi All,
>
> I heard the Golf 90A alternator is an almost direct drop in to the
> vanagon (you just have to use your old wheel). Anyone know what year
> golf and the golf part number?
>
> Also, someone had a website on the golf alternator swap. Anyone have the link?
>
> Chris
>