Check your cap and keep the air out of the system. If you changed to new intake gaskets, chances are the material used is now compatible with the OAT coolant. You still have a waterpump that is prone to cavitating it though. No fix for the pump. The next generation V-8 engines solved it with a new pump design.
Many are living with OAT coolant, just like "Gremilins" heed the warnings: "Don't get it hot", "Don't give it air", and what ever you do "Don't feed it after midnight, no matter how much it begs!"
It will turn evil on you