Crane it over the fence?
I dunno as I have not yet seen the entrance but anything free seems worth taking a punt at to me.
Bloody great big tree in the way, and adjacent to the track on the other side isn't where I'd want it anyway.
You'd have to see the place to understand what i mean really. It would have to be dragged into the Swamp, and that would be nigh on impossible due to the soft earth.
It currently belongs to some 'caving enthusiasts club' apparently, but the landowner has been told by the council to get them to get it removed for some reason.