It's been a few years since I had a alternator apart. If I remember correctly, there is a spacer between the front case of the alternator and the fan assembly. This spacer will give you the needed clearance.
Tim
"Pay attention to the details! It ALWAYS pays off."
1949 Chevrolet 3100 Series 1/2 ton Pickup 1964 Chevrolet C10 (Ol' Yella) (SOLD) 1958 Chevrolet Biscayne 2 door (SOLD) 1970 VW Beetle