I know I am reviving an old thread here, but I have a question on topic. Can I ask you to elaborate some on the plug filling of the stock disk recess? I ask because I have recently acquired a sporterized 1942 Lithgow No1 MkIII, that I will be restoring. The buttstock has a plug in the stock disk recess. Before I go and look for a replacement disk, I would like to be sure that I would not be making a serious mistake by removing the existing plug.