Yep. That's exactly what I have/had on the top of the fenders. Thousands of them. The problem with blasting is that the metal is not very thick and all the old Jag guys on the forums say DO NOT blast the metal. SOOOOOO, other than replacing the fenders, which is NOT an option, I have no idea what the best possible solution is. Some say use the product, some say strip it and use OSPHO, some say blast, some say wire wheel, etc, etc. Out of all the choices, I just have to bite the bullet and go with what Barry told me to do. It's a crap load of work and in the end may STILL end up like what happened to you but it's the best option. So I've got half of the car back to metal and will have it all sanded again by the end of the day, will OSPHO it tomorrow and by the end of the week will have it in epoxy primer again. Got nothin' else to do. Sh*t happens.