Have had a variation of this model Kohler for 10 years. The seat broke so I thought it would take 5 minutes to replace it. Not so! I can't remove the bolts. They turn freely in either direction after I finally dislodged them with a screwdriver, but I can pull them out or tighten them. They are stuck. Can I remove them without breaking the toilet and then be able to install a new seat? Or do I need a new toilet?? TIA!