I have a 10inch tube that I purchased in 1990. It has now followed me through 4 cars and is entering my 5th. The previous cars have all been a snap as they've had aftermarket stereos. My 99 Explorer has a stock CD player and I need help locating the best source for the audio signal and auto turn on/off. I have seen an in-line harness that will add RCA outs and an amp turn on lead to my stock deck but its $80. Any help is appreciated. Also wondering why there is no copy of install/instruction manual for a vintage tube such as mine on your site? Thanks.