High raised C&C

I was thinking of putting a C&C cage ontop of my 5x2 Hutch which houses my two 6 month old boars Sunshine and Twinkle. However, my husband is rather weary incase my other two boars Cuzzy and Eccles gets out and end up falling on the floor.

Has anyone sucessfully built a high level C&C Cage? I will fit it together with the fittings that the grids come with but will they have to be reinforced together to prevent escape?

Currently Cuzzy and Eccles are in a 3x3 C&C in my living room and live on fleece.

Thanks you for reading and I look forward to reading your thoughts and opinions.