SAN FRANCISCO -- A man who told undercover agents that he wanted to carry out a Christmas Day bombing and shooting attack at a popular San Francisco tourist attraction will receive a 15-year sentence after pleading guilty in a federal case.Everitt Aaron Jameson pled guilty Monday to attempting to aid a terrorist organization under a plea deal with federal prosecutors.Prosecutors say Jameson, a former tow-truck driver from Modesto, California, told the undercover federal agents that he planned to use pipe bombs to channel victims into part of Pier 39 so he could shoot them.Prosecutors are dropping a second charge of distributing bomb-making information under the plea agreement.Each charge carries a maximum penalty of 20 years in prison.Defense attorney Charles Lee says his client was having second thoughts and didn't actually take steps to carry out the plot.