I have about 35 old starter cores . Some have some mild corrosion but make for rebuilders. My question is are there any rare number or date codes that I should look for ? If so what are they and where are they located?

There are two.

One on the snout & one on the barrel.

If they have not been rebuilt before (cases blasted, OE details lost) Jim Ridge buys cores to restore for his clients.

Linky-thingy;

http://www.dixierestorationparts.com/restoration-services.html

Thanks for the link Barry .i have bunch of alternators also. I will contact them. BTW I will be sending you about 25 fender tags next week.

Jim is a great guy, give him a shout for sure.

Thank you Ken! Eager to see them.

Look up the dates/codes yourself online before giving them away for core prices. Some are worth good $ even as a core.

Thanks for the advice. I will have to educate myself a bit on date code meanings and locations. Now that I think about it I have water pumps,dist,radiators,wiper motors, window motors,etc.