Most of the threads suggest people use the LHS infill panel and the circular indent meant to house the optional power outlet. You do have to extend the cabling to that. Looking at your photo I wonder if the cable would allow you to cut a small circle in the radiator mesh and mount it there with the barrel sticking out and the rest behind the mesh. I doubt the heat could cause a problem.
If you look at bottom of this page you will see 5 Similar Threads for more examples of how people have achieved what you want to do.