Picture/Plaque Concealed Mounts

We wanted to mount an old carving of the Green Man without damaging it in any way. Two each of these mounts were printed and screwed to a piece of cloth covered MDF. 

The small fixed ones were lined up for the lower edge of the plaque and the slotted ones fixed at the top in such a way as to allow the plaque to be placed between all four brackets and the top pair slid down to grip the plaque into place.