I don't think Malcolm ever had two Martins. He used to have a Martin D28 and a 12 string Guild. It appears from a posting above that he sold the 12 string to get the money to visit the States.
Later he often asked me to sell him my Harmony 12 string a cheaper guitar which I bought from Geoff Bradford but Malcolm still enjoyed playing it. I held on to it for some years and I later gave it to Ced Thorose.