EL PASO — You may want to avoid downtown El Paso this Sunday. Traffic will be a mess. Several downtown streets will be closed to traffic from seven a.m. to noon while the city installs a new public safety communications system on the top of the Wells Fargo building on North Kansas Street. Some radio equipment and a generator will be moved by helicopter. The streets highlighted in red will be shut down while the work is performed, about six blocks surrounding Wells Fargo.