GCap Media shares are no longer traded because the company was bought out by Global Radio, paying 225p per share.
GWR Group shares are no longer traded because the company was bought out by GCap Media!
(I'm unable to track down what was paid for the shares but, in the years prior to the 2005 takeover, they'd been trading at roughly between 135p and 230p).
SSE shares closed at £12.17 per share at the end of today's trading.
Also it is possible that the 6 shares G Cap were given in exchange for the 10 shares GWR;-
GCap Media was a British commercial radio company formed from the merger of the Capital Radio Group and GWR Group. The merger was completed in May 2005.