Sounds to me like one of the shields is not mounted properly, or sitcking out like mine was. I had this problem but mine was hitting the tread. I found that one of the splash shields behind the tire to guard water from getting into the engine compartment needed to be pushed in toward the engine. I would say to turn the wheel to the direction that it squeals and look in the wheelwell to see what the tire may be hitting. It'* probabally not going to be really noticable (look hard for wear marks in the plastic shields) since it was worse before the alignment, and now its just a light squeal. Start with the easy stuff. Let us know what you find.
1993 Bonneville SC SSE With Supercharged Badges, Black and Gold, CAI, 180T, TR-55'*, 2.2 Pulley, Jet Stage 2 Chip, Ceramic coated PEM'*, Magnaflow, Flowmaster 80, Megs Tips.
1995 SLE (Wifes), White and Gold, CAI, APN, Magnaflow, otherwise stock.
1966 Ford Ranchero, 312ci 60 over block decked, GT40P heads Milled, RPM Air Gap intake, Holley 600, MSD Billet Dist., 6A Box, FlowTech Shorties, C-4 W/Shiftkit, 8" 4.11