Character Prone Collision Solution

Hello mates.
I have been trying to get a suitable collision for my character when it goes prone. I am using a character blueprint derived from 3rd Person template C++ class. Animation and system works just fine.
I have tried many things and failed. Because from what I could gather around: Character class only allows a single Collision Capsule, that capsule can not be disabled, can not moved. You can modify it’s size via blueprint/ C++ but that is it.
For example you can not put a Collision Box, and switch between capsule and box depending on whether character is standing or prone.
So I wanted to ask you mates here. You guys have any idea how can I make a suitable collision model for my character ? For example can I just use character’s skeleton/bone capsules for collision ?
Here is a simple pic to visualise the problem.