For $130 more you could send it to Stan Warren in Oregon who will modify the optical output and install a custom cable directly to the circuit board on the Aiwa that goes to the optical input on the DAC.
Still a great transport without the modification.
If you are not using a Delta Sigma DAC with an optical input, then a used Rotel 970 or 975 with the Phillip CDM-9 transport will work fine. There is also a Rotel transport with the same mechanism that was made for Rotel DACs.