Hi, I have a Nikon-m43 adapter which is very firmly stuck to a Sigma zoom lens with Nikon mount. Or, in other words, I am unable to remove that adapter from the lens. The adapter is a Big_is Nikon AI F Lens to Micro 4/3 M4/3 Panasonic G5 GF1 GH1 Mount Adapter (http://www.ebay.com/itm/400325231922) and the lens is a very old Sigma 100-300 AF/APO (pictures at http://www.tutti.ch/aargau/foto-vid...f-apo-75-300mm-fuer-nikon-kameras_3805878.htm - I am not the one selling, just linking for the good photos of the lens). I am looking for any and all suggesting on how to remove the adapter from the lens. Many thanks!