on all stereos i have worked on there is a wire off the back of them, not connected into the block, like the amp remote. it is usually orange and also usually has power ant wrote on it or on a lable on it.( it may be blue with a stripe or solid blue depending on amp remote colour it can be various other colours but never in the usual block thing). Do you know which wires come off the power antenna into the head unit compartment? if so post exact colours and markings on them.
