There should be a spacer between the each plate and the lugs on the frame, or have you just left them out for the photo
spacers not in but that is as far as I can get bottom to close but the boss on the motor is to wide
Cut the inside sleeve on the right side bracket ( took of about 3/8 and it fits fine ) need to do a lil filing in the 1/2 for a better fit ,,bot that as far as the bottom will close,,may machine a lil off the motor case so it sets right,,almost seem the mounts should be different ,,jusr don't really know. and cannot find of 54 55 part #