Nope, not wrong. Just a mighty amusing mixed metaphor, according to me.
Ummm!, I hate to tell you but God did not do away with circumcision of the heart, unless you think that Paul was just kidding in Romans. I know that Romans is a tough Epistle for the haters of the Bible to swallow. Paul was such a comedian. He should have appeared with Bob Hope! The verse you are abusing in Corinthians is talking about that little piece of flesh between your legs and Deut. is talking about the heart.
And they both talked about the necessity of keeping the commandments, which answers your next question, as does Deuteronomy 30:1-6.
So, please answer the question. How is this accomplished?
OK, so how many actually were able to keep the commandments? Is there a single person in all of creation that actually kept the commandments? Is there a single person who has sought God with his whole heart? Note that we are talking about the strength and righteousness of the FALLEN man whom you say can circumcize his own heart.