Use a text editor to edit the "config.cfg" file in the "18 WoS American Long Haul" directory. 

Changes these lines: 

 uset g_console "0"
 uset g_developer "0"
 uset g_police "0"

 to: 

 uset g_console "1"
 uset g_developer "1"
 uset g_police "1"

This will (in order), enable ~ to display the console window; enable developer mode; and 
disable the police. To activate the remaining cheat codes, press ~ during game play to 
display the console window.