The short answer is NO. The mounting bracket for the TR6 calipers is different then the TR3 mounting bracket. The TR6 bracket has it's caliper mounting holes spaced farther out then the TR3's. Also, which calipers do you have on your TR3?? The earlier calipers are a single casting with the bridge pipe and uses an 11" rotor. The later ones use a 10 3/4" rotor. If you have the smaller rotors, you could theoretically use the TR6 bracket with a TR6 caliper, but then it would probably be best to do that to both sides.