I don't think you should get the pit simply because both of you don't want it. same for the yorkie.
I don't mean for that to sound harsh, but if he doesn't support your decision to get a yorkie at all, and you don't support his decision to get a pit at all, maybe you should both try to settle on a different breed.
Do I think pits and yorkies can live together? without a doubt. But with pits you have to go back into their lines as far as you possibly can. They have to come from the best breeders you can possibly find. Because they're not mean dogs, they're just very very powerful. If you can be sure that they come from amazing lines, then your yorkie will be much safer. Though I will say that you shouldn't let them play together without supervision, because even a play bite from the pit could do some serious damage.
I love pitbulls, but people who don't really love them (you said your hubby only wants one because he doesn't want you to get a yorkie?) and people who don't really want them shouldn't get one. period.
On that note, I have a lab. he's the sweetest dog ever, why don't you give him the idea of a lab?
and that's all I'm going to say on this subject right now because, hate to say it, but sometimes I feel like I'd be better off talking to a wall if I'm trying to defend pits on this forum.