swapping 5speed to Auto for race purposes only

there you go; the 111 says WP of 9.15, so at 3660 that would be 400 on the nose and with SS suspension should be good for about a tic under 12.00.... at 12.72 you are about right for street suspension. Maybe a hair slow with slicks, Caltracs and the proper trapping gears. So you could be right about the scales, being heavy.