Again a question… I have installed a final stage on the last WE and stuck to the Concert 2 (no Bose). I thought the boxes are all hanging directly from the radio output, BUT: I have seen that only the front-speakers on the radio were serekt jammed, the rear-speaks are hanging on the “line out”!?! The friendly one told me that the “not Bose” TTC also had a standard final stage – looks quite like it too, but was new to me. Is that so, did you have that too??? Tulura