seems to me the best approach would be to completely redo the pump on any aio kit but idk.
This previous AMD Thread on the 4700S kit one of the User was designing a better CPU Cooler for that processor.
No 3rd Party CPU Cooler will fit on that CPU board: https://community.amd.com/t5/general-discussions/lack-of-support-for-cardinal-4700s-desktop-kit/m-p/...