Child Support vs. Title on my Car?

I have custody of my kids. Kid's dad is of course in arrears. I am planning on filing taxes for BOTH kids, instead of the just the one that is listed in the parenting plan (I can do that, if he is in arrears) come tax time. BUT I own a car, that is listed with both my name, and his name on the loan. I finish paying off the note early early February. Problem: When I got him to sign a paper, stating that no matter what, he would sign over the title to the car once it's paid for, I forgot to have it notorized. I dont want him to know that it's not notorized because I dont want him to know he has any leverage over me. I plan on getting the title to my car, (which he will sign over, if everything is cool between us), but I also plan on claiming both children and ALL the daycare I pay for..........he also should be paying for dental insurance that I am paying for now, but I dont want to include that when we go to court to modify child support payments, because he may not sign over the title
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Didn't they state who got the car in the divorce, they did on my cousins. If they did and it was you should have no problem. I would think if you have been making the payments since you split that would go in your favor also.
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