bluebell hutch

Hi! I have the Bluebell XL hutch for my guineas and looking for ideas on how to modify the big gap area upstairs that is above the ramp, and seems totally unsafe if left open. I currently use the shelf ledge from an old ferplast cage, which fits nicely and creates a bigger open area upstairs...

Does anyone know the external and internal measurements for bluebell 6ft xlarge cage? I have the measurements for the 5ft one (attached below) but need to know the measurements like them for the 6ft one.

Morning all, I wanted to post what I have been up to with the piggies new Mk3 shed - which I have fully insulated with thick polystyrene sheets and a top layer of silver faced bubble wrap - there are vents and I am right next to the house with this so WILL have power in there to heat the shed...