Ok - unless things are different wherever you are....
The insurance is for the car - not for you or for STBX. Talk with the insurance company; you may be able to take his name off the policy even if his name is still on the car. (Just don't let him drive the car after that. I know my insurance company still covers my vehicle even for someone else driving it as long as it was with my permission, but I don't know that's how it works for all insurance companies. And even if it does, they might question it if you deliberately take him off the policy and then later there's an incident with him as the driver.)
But as far as the title to the car goes - just focus on the big picture. As long as he's not trying to take the car from you (i.e., as long as you aren't afraid of waking up one morning to find that he took the car), there's no reason to worry about this until you get an agreement in place.
By the same token, don't "sign over" anything to him until you have a signed agreement either. It's just protecting your interests.
Example: during our D, my X asked me to sign so he could take out a loan against his retirement account (similar to a 401K). He needed the money quickly, and we had already agreed (verbally) that we would each just keep our own retirements, and sign over any rights to the other's. He had done something stupid, and was in danger of losing his job if he didn't come up with the money quickly (needed to pay back bill on a corporate credit card that he used for personal use against policy).
I refused to sign it. Or, more accurately, I told him I would sign it just as soon as he signed our settlement agreement. We had agreed to everything initially, my lawyer had written it all up, and then he started balking because the skank was agitating that he should be getting more than he was in the settlement.
Honestly, it didn't matter to me at all if he took out the loan, since I wasn't going to have any claim on his retirement and he none on mine anyway. But.... my fear was that he would default on that loan, thereby owing penalties and taxes on the money, and since I had signed that he could take the loan, I would be liable. Or that after he took out the loan, he would default and then try to lay claim to half of my account, showing that his had a much lower balance and that getting part of mine would only be "fair".
In fact, I did use him needing that money as leverage to get him to sign the settlement - but I was only pushing him to sign what he had ALREADY agreed to verbally. I knew that once the settlement was signed and in place, I would be able to argue that he could have taken out the loan without my signature - that I had only signed to expedite it for him, and that we already had an agreement that said we were each entitled to/responsible for our own retirement accounts.
Bottom line - as long as there is no special reason you really need his name off of it, as long as it's just because you want his name off... don't sweat it. But do remember - you play it the same way, and don't give on anything either until the settlement is signed. Doing that is just a safety measure. Even though you know that you have no intention of trying to get more because his name is already off of your car, his lawyer can't know that. And by the same token, you can't trust that they will deal honestly with you if you give on anything similar.
ETA: Definitely talk to the insurance company. If your rate is higher because he is on it, you have a couple of ways to go. If you can take his name off and he won't have any penalty for you doing so, then just do it.
Otherwise - find out what, if any, difference there is in cost because he's on the policy. And if there are penalties for him not having insurance if he is taken off the policy. And then present him with the following choices:
- Sign over the vehicle,
- You'll remove him from the policy, and he'll have to pay any penalties for insurance violations or get his own policy for the vehicle, or
- He can pay the difference in cost for keeping him on the policy.
All that being said - if doing that is going to cause trouble with him and make it more difficult to get the settlement, you have to decide if the extra money (if any) for having him on the policy is worth it.
As Take2 said - this is a business transaction at this point. I know it doesn't feel like it, but it is. Take the emotion out of it, weigh the different possibilities, and do the one that benefits you the most.