From the internet:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">where can I find complete delco radio plug and wiring harness for 1972 Chevelle ss? I think I have a u57 radio (AM/ 8-track stereo tape player). The service tag reads 21APBT1 and the product number is 7933271. I have all four 10 ohm speakers and radio, but no radio plug or harness. Looking at rear of radio I see two rows of what I call male spade connectors. Top row is 5 wide and bottom row is 4 wide. Any help as to where I can find the correct parts would be greatly appreciated. Thanks, B Davies</div></div>
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This from Team Chevelle...