there are 2 issues using crop specific lenses on a 1.3...
the first is that they may protrude into the mirror assembly because the mirror on a 1.3 is much bigger than the mirror on a 1.6. If this is the case you CAN NOT use the lens as it will break the camera. If you don't know what this means I suggest you don't try it.
the second is that optically the lenses designed for a 1.6 have a smaller image circle by design because the sensor on a 1.6 is significantly smaller. If this is the only reason it won't work then you can use them, just expect black or very dark corners and edges.
But generally if it's a cropped lens, you'll at least run into the second issue, so why not just use glass designed for FF? Also the mount is physically the same size (otherwise you wouldn't be able to use "FF glass" on a cropper) but it's marked different for EF (red dots) and EF-S (white diamonds).
