I wrote a Tech Tip in the newsletter – July 2003 about this. You should be able to open that issue on the Membership page.
I used a mid 60’s style Ford alternator with a bolt on electronic voltage regulator. I made my own bracket to mount the alternator. The only real modification I made was to make the Original Voltage Regulator a junction box so there was no mess of wiring at the VR location.
The alternator has worked just fine since install.
If you have question contact me – email@example.com