A:
The truck's radio must have an FM mode to provide an otherwise unused "channel" to receive the XM signal. An 'AM only' radio will not provide the proper interface. That '76 Chevy is probably worth the purchase of one of the integrated AM/FM/XM/CD units. Try one that does not require "in-dash" installation to preserve the original truck radio. By the way, most AM radios will be overwhelmed by Radio Frequency interference (i.e., static} in the presence of the signal produced by an XM Radio converter. If you plan to used the AM radio, make sure that the FM converter can be switched off when the XM radio is off. Good luck.