ironhead3fan ,,,,,
sorry for the confusion ,,,, the J&M amp should work fine with your Radio Shack head unit ,,,
wiring harnesses and all should just plug right in ,,,,,,, just like they do with the HK radio ,,,
you could even use the RCA's on the J&M amp, for the signal input from the radio, if your radio is so equipped ,,,,, then just flip the switch on the J&M amp to RCA input mode ,,,
Just let us know how we can help ,,,,