I'm planning on upgrading my original 55 amp external alternator to a 100 amp internal, this will help carry the additional amp load for my spal fan, digital dash, stereo, etc. on my 1964 Impala (327 cui) with HEI upgrade! I plan to use a 3-wire conversion kit: http://tinyurl.com/d4j6chs Few Questions: What year "internal" alternator" should I consider upgrading to? I don't want to make any modifications on the mounting (bolts), etc. Example: Could I purchase an 85 Camaro "internal" alternator and bold it right up without modifications? What do the numbers represent in "12SI" alternator term versus 10SI, is that just a model number? Will I be required to remove my stock voltage regulator or can it remain in the original configuration regardless of the internal alt upgrade?