Does anyone have experience installing hood pins in an aluminum hood.  The instructions call for a 3/4" hole saw.  The teeth on the hole saw I have seem agressive for the aluminum, afraid it will tear rather than cut the metal.  Are there hole saws made exclusively for metal with a finer tooth pattern, and maybe the one I have is for wood?  

Not sure of the hole saw but why not try using regular drill bits for metal.  Step up from a 1/8 inch to 1/4 then 1/2 then 3/4.  Just a thought, not an expert.
I have a 2007 Shelby GT with an aluminum hood.  I replaced the stock hood pins with the upgrade Shelby hoodpin setup.  I did have to slightly trim the aluminum hood to get the new pins to align perfectly.  The original holes were more of an oval rather than round due to the angle and length of the pins as they go through the hood while closeing.  If you are working on a new model hood, keep in mind to bend the pin brackets so the top of the pins go toward the front of the car at a very slight angle (my guess is around 5-10 degrees).  If you have an older car, then I am not sure.
Hope I am of some slight help.