I use the Moroso water pump drive (coming off the driver side of my engine, mounted to the driver side water pump bolts) and my alternator is in the standard location (passenger side). Works fine for me....but I have had the same issues with keeping belts on. When I run 1/8 mile the belt hangs on no problem (shifting at 6500), but when I run 1/4 mile I cross the stripe at about 7200 and I tend to lose the belt.
Edit: Car is a 67 Barracuda if that helps.
