I did this on my 68 last summer and it greatly improved my idle voltage and overall charging system performance.
Of course I didn't take any pics, and the car isn't here now but I can describe the process pretty well.
I used a CS130 from a 1993 3/4 ton 454 4x4 Suburban that I was already taking TBI and harness from.
It has the mounting points at 6 and 12 o'clock and the charge post is also in a convenient spot. The other bonus is that it has a single wire for the alternator exciter circuit, that makes it easy to install in an external regulator car. The exciter circuit is the one that turns the alternator on, it typically has the charge indicator bulb in the circuit.
Here's what it looks like. This pic had the wrong mount clocking, but you get the idea.
http://store.alternatorparts.com/cs130i-a105-amp-iceberg-series-finned-housing-alternator.aspxIf you are grabbing one from the boneyard, get as much of the exciter wire harness as you can. That's the plug in connector on the top/side of the alt. It's the right kind if it is a long connector with only 1 wire coming out. It's actually a 4 pin connector but you only are using the "L" terminal for this particular cs130. Other applications use the large S terminal also, I like this one because you don't need to.
Here's a pic link
http://www.americanautowire.com/faq/wp-content/uploads/130-144-connector.jpgTo physically mount the cs130 is easy.
The mount points and dimensions are almost the same as the old 10si the Caddy came with. I had to shave my bottom mount spacer just a hair, but that's it.
As far as the pulley goes, you will need to swap your v-belt pulley to the new cs130. DO NOT swap the fans. The cs 130 internal and external fans are made to rotate ccw. If you put the 10si fan on, it WILL overheat. Ask me how I know.
Use an impact tool to swap the pulleys, anything alse is an ass-whuppin and may break something.
The wiring is easy too.
The charge back wire will be in the same spot. This is the large gauge red wire that goes on the threaded post on the back of the alternator. I recommend upgrading it to a 6ga or 4ga wire to handle the added current. Attach it to the new cs130.
The Dark Green wire that was on the 10si charge post won't be used.
The regulator wiring:
Disconnect the 2 wire connector from you old alt and set it aside, you won't be using it. The Dark Green wire to the charge post will probably be loomed up with this connector. Again, it's not needed anymore.
Remove the external regulator. When you do there will be 1 or more black ground wires that were attached to the body of the regulator. Find a new spot to ground those guys again. On my car they were for the lighting circuit and the r/f lights were all dim without this ground hooked up. DOH!
The harness connector for the external regulator has 4 wires. Mine were Dark Blue, White, Red, and Brown. Check your particular year wiring diagram to verify you are using the charge light circuit for the exciter.
You will only use the Brown wire, it is the one that goes to the charge light in the cluster.
A generic spade connector will slide right into the Brown wire terminal on the harness plug for the old regulator, that's what I used.
You then run a wire from this Brown wire terminal to the new cs130 "L" terminal plug. This is where it's handy to get a good length from a donor car so you don't have a bunch of splices.
Secure your new wiring, tape up the old regulator connector, and tighten your alternator belt.
Crank up the Caddy and enjoy!
As a note, the wire colors may vary with different years, but the basic idea should be the same.
Also, this was done on a car with an unmolested original wiring harness. If yours has been hacked or had changes made to the charging circuit this may not work.
Check to see that the unused wires have no voltage when you're done. If you did it right (and the various years wiring is the same as the 68) they should be dead. They aren't connected to the cars' electrical system any more, and you can remove them from the harness to tidy things up.