I am finishing a Painless Wiring kit in my 69 convertible. I have the wires set up to use an internally regulated alternator. I was at autozone trying to get the alternator and all the kid could come up with was an externally regulated alternator. What year did GM go to the internally regulated alternator. Any help is greatly appreciated.

Bob

In the attached link there is application information on alternators. Depending on what you need and what you want to pay, it will get you what you need. Both the 10 SI and the 12 SI will fit. Read the part about alternator "clocking". Easier to buy one "clocked" correctly. The 10SI's tend to be cheaper.
http://www.madelectrical.com/electricaltech/delcoremy.shtml