The heater core in my 68 American leaked and I replaced it with a 69 Jav-AMX V8. I remember the one in my 65 American leaking awhile ago and I replaced it with a 73 or so Hornet. The one in my old 68 Ambassador was replaced with a 73 Jav. So.... I would think your Ambo might take a Jav just like mine did. I would pull yours, connect the two hoses with a union so you can still drive it, and order a 68 Jav V8 core, I know they are available, I just ordered one for a guy and got it the next day; cost was $31. Compare the two....Russ __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com