not legal, in fact if a shop owner told me it was, i would NOT get my exhaust done there. At least if he had told you that it wasnt legal, that would be decent. There is no reason to mess with the cats on these rangers, there so many because they are a higher flow than they used to be. The performance gain would be negligible if anything, and the sounds wouldnt increase THAT much since on the SOHC youre already going through 3 other cats anyway (i think there are 4 total).
Bottom line is, not legal, no reason to do it, shop owner lied or is ignorant. DONT DO IT!