I am late in replying, however for those who asked here are fotos of the GM
Delco 80 amp alternator installation on my 2600 Sprint. I have also installed
the same alternator on a '69 Lotus Elan and on my '76 Montreal.

On the Montreal the Delco unit fit onto the existing mounts, however on the 2600
(and the Lotus) new brackets had to be fabricated. I am sorry I cannot furnish
better fotos of this, but basically the new alternator is moved rearward around
22mm ( 7/8") so the pulley lines up correctly. This is accomplished by using a
spacer of this length and a longer bolt at the top (plus a new arm) and
fabricating sort of "Z" shaped spacer brackets at the bottom. Otherwise the
Delco mounts in the stock fashion. For these spacer brackets and the arm use
1/4" steel stock, and/or buy some appropriate-looking pieces from the J.C.
Whitney catalog to use as a starting point when you order the alternator. I did
this, and the top arm is a nice chromed piece that only required shortening.
Another place to begin looking for pieces like this is at your local junk yard.

On all 3 cars the pulley that came with the alternator was used, and the stock
2600 fan belt was reused, too.

As I mentioned earlier, there are many advantages to this swap: built-in
voltage regulator allows you to junk the old mechanical one and the associated
wiring, much greater power output, dependable, economical price, easy
availability (at least in the US and Canada), pretty easy to fit. Disadvantage
is you no longer have a "Generator" light.

Tom Sanor

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