This does of course go to the fact that you have to work on the GM cars more often. Ask 929Pheonixsquid about stuff falling off one driving it around.
Seriously though, a head is a head. You will learn a lot of stuff about cars regardless of what brand you learn, it will be helpful. I still need help adjusting timing, and stupid crap like that that should be second nature by now.
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1997 Mustang GT "The Freak" - 13.80 @ 101.70, 2.07 60'
1995 Honda VFR750 - not much @ really fast (actual data pending.)
1964.5 Mustang 289
Rice Haters Club Member #13