A littlle off-topic, but Son of Weldangrind's '91 Ranger VR packed it in, which was due to very corroded battery terminals. I found another alternator at the boneyard for cheap, but I was pleased to find out that the VR is mounted on the outside of the alternator housing. I have an eBay replacement (including the brushes) on the way for $23.00.
I wonder if that type of VR could be easily adapted to a bike?