An older thread but I've got an idea of trying to wire a rf limited EC-2018 xtr for the apollo ii. So I sold my apollo to a friend and am thinking of getting another for the car because I just can't find a suitable mounting place for the 447hpc2. In theory I could use an adapter but with echo because I like just a hint on an am only radio, I don't think the mic built in talkback will work. Please correct me if I'm wrong. Why talkback you might ask, well I need to know where to set the hint of echo. Just an idea I had while I was at the gym because for some reason even there I'm geeking out on hobby ideas.