Sealer issues...

[WeepingPiano]

I ran out of Testors the other day right as I was getting to my last two ponies of the batch. I mentioned it to my mom since I am not going into town for a while and she hands me a can of clear spraypaint. I told her it would not work, because spraypaint does not work on ponies, but she got a little irritated with me and said I was not putting the spraypaint on the pony, I was putting it on the FBR. To humor her (and prove her wrong) I used it on the last two ponies.
 
Here is the thing, one pony actually has a nice seal on it, but the other is still tacky. BUT its head is not. Why? They were sprayed at the same time. I could understand different ponies acting differently, but the head curing just fine and the body not?
 
So what do I do? If I buy a can of Testors and spray the tacky pony, will it be able to fix the tackyness or do i need to start over?

[Pythia]

Sometimes heads and bodies seem to be made out of slightly different plastic - hence mismatched heads/bodies, and heads and bodies that fade differently. That might have something to do with it.