I found a $100 product on the Internet … Then I will flush it, refill the radiator and drive off into bliss.
You already know the answer to this one don’t you? If not I have a bridge for sale.
I am going to walk into the mechanics shop and ask them to do it. Do you think my mechanic will have a problem doing this?
If they don’t have a problem with it, get a different mechanic.
First, don’t assume you are correct about what is happening to your car. Bring it in and tell the mechanic what you have observed and tell them of the prior head gasket issue. Don’t suggest what you believe is wrong, that’s their job and they are better at it than you. They are right there and they can do the testing and looking we can’t do directly.