i recently bought a pair of Specialized Sport Mountain bike shoes, which i planned to use with my Crank Bros. mallets. installed the cleats and found that i couldn’t clip in. i realized that there was not enough clearance between the cleat and the grip on the shoe. i have small feet (size 39) so is this just cause by the shoe not being wide enough? 
you may need to use shims (they come w/ the cleats) to raise the cleats, or you can cut away some of the tread
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i have the same setup except i have size 40. i used the shims to get around this problem.
Time for some surgery? I think the crank bros cleats are far wider than SPD rather than the shoe is too narrow - I would certainly just remove a little bit of the rubber to allow free access & float
you may need to use shims (they come w/ the cleats) to raise the cleats, or you can cut away some of the tread
i used them; they are on them. you can kinda see them in the pics.
Exato knife or Dremel time…
Seen this before with a friend’s shoe (adidas mtb shoe). If shim doesn’t raise it enough, trim some fat with a dremel or whatever depending on the softness of the rubber.
either use another shim under the shim you have there already or cut out some plastic or gasket material and use that as a shim too, that will work out, the mallets have a higher then noraml side profile to grip the sole and you need to just make the cleat higher by a touch to get it to work. I have nearly the exact same setup on my downhill bike and the extra material did the trick
either use another shim under the shim…
This is extremely common for MTB shoes. Just trim the plastic cleat until it’s wide enough to accept the pedal cleanly. Drellel tool or exacto knife does the trick. Riders who use a wide interface like Time Atac’s need to do this all the time - it’s normal.
DO NOT add more shims - in fact, avoid using shims if you can. Adding shims increases the torque on your cleat, and increases the forces on your mount screws. Shearing off a cleat screw is fairly common with hard MTB riding, so the last thing you want to do is make it easier. Besides, you also need to raise your seat if you add more shims, and it’s better to keep the center of gravity as low as possible on a MTB.
i just tried the shim thing, didn’t work. i’ll try cutting the side later