If you're sure you didn't exceed the two 90 degree increments, adding another 10 degrees or so shouldn't hurt anything. I did this myself for a different reason with no ill effects but I don't recommend it unless you're willing to deal with the worst-case scenario - pull the head again, check bolt length, re-install with a new gasket. Next time, I'm getting one of those degree indicator thingys so I can tell when I've exactly hit 90 degrees...