Use these plug in base attachments to make your lifesize mounts removable from their base.
Insert (glue / bondo) the black outer piece into your base, thread the inner white piece onto your mounts threaded rod, then slip the white piece back into the black piece in the base. If your form has wire instead of theaded rod, simply bondo the wire into the white piece.
THREADED ROD SIZE ⅝"
PLUG IN LENGTH 2 ¼"