Kurt (or Ed or anybody),
Help me understand the difference in the numbers here. The numbers Mopar lists are 8 digit AC Delco replacement part numbers, right? I've never seen a radio catalogue P&A, so I do not know what it lists. But I do know the GM P&As from 64-68 list 6 digits (not 7?!?) replacement part numbers that run from 985xxx to 987xxx. Sooo, beyond the batches of numbers you mentioned above, there really is "nothing beyond that" AND other than they may refer to the same part (replacement) supplier numbers and GM numbers had no corresponding pattern?