I had the disc tab done by Patrick at Limit Fabrications.
Fantastic service and result, couldn't be happier. Patrick made custom tabs to fit the caliper within the rear triangle and enable the use of a larger 160mm rotor on the rear, as well as eliminate the need for a brace to be added.
The welds are perfect, and the cost was less than half of what Enigma quoted. Highly recommended titanium craftsman.