i made 4 small 2"x2" aluminum "L" brackets, and used them at the 4 rear fender mounts, undo the bolts, slide them under the plastics, slide your box in place, get the brackets slid so they are touching the box, and lined up with the holes, mark and drill all holes, put the fender bolts back in and use 4 small bolts and nylock nuts into the box, this also allowed me to align it with the carb better than the factory mounts < side to side, and front to back, have it connected to the carb while mounting it to get the distance right and relieve stress of the boot < siliconintakes.com
reducer----2.5"x 2.25" , get the clamps too, awsome stuff !!!
heres the only pic i have right now, the 2 rear ones mount to the back .....................