I don't have one, however, I've been shoping for a trans. Seems most builders charge a $300 or so core charge. It might not be worth it, by the time you find one, pay for shipping, etc. Brian Holfer on here had a great price on a trans with no core needed, I'm just too broke to by it. I guess, before you go and get a core, you might just want to go to a good Buick trans builder and look at your options.