Likely, the repairs would be similar to other Canon 5D repairs, and would need to take off the back panel to access it. I know my Nikons have the parts attached to the inside of the back plate and can be repaired. Just go slow when opening, and screws often are hiding under the rubber grips, I have found.
I don’t see any repair guides for the Mk IV. If you have the time, making them would help everyone in the future, and isn’t too hard to make on here.