My just acquired Champion Team has a 74 stamped Campagnolo back derailleur, a 4 inside of a diamond on the crank, the bb has the numbers 7D4 (if you read it as a year it could be hinting to 1974), it also has an E, and lastly what it appears to be a 21 (I've looked very closely with a magnifying class, and it lookslike a 21. Lastly, the serial number on the left drop out is 2918328. Thanks for all of your time and help! It is truly and sincerely appreciated.

Flash