How to Remove Mud Flaps

Can someone tell me how to remove the rear mudflaps for my Discovery 2? Though a simple job, I can see that there are two cross-headed screws on the outer side, but specifically it is the two 'fixings' directly behind the wheel that I can't figure out. What are they? Mine are heavily rusted, but they look to be either rivets or hex screws, though I can't get a hex screwdriver to fit.
Thanks,
Andrew

Rivets, I think you will need to drill them out.

Unless they were changed at some point, the mudflaps and the mounting brackets are all held in place with rivets. The rivets are not easy to remove, even with a drill so you might need an angle grinder. For the brackets, you have 2 rivets at the top, one on the side with the body panel and another one at the back with the diagonal support. The mudflaps are held with 2 rivets against the mounting bracket and 2 outer screws on the body panel. Can't remember if they are Phillips or Hex.

All I can tell you is that if the mounting brackets are rusty, they will likely break or get damaged during removal so it would be a good idea if you order a set before you start. It would also help if you apply anti-rust treatment before installing as they corrode again in no time.

Grind heads off then pry the bracket off