LAKE ELSINORE (CNS) - Both sides of the Ortega (74) Highway between Lake Elsinore and the Orange County line will be shut down again tonight and remain closed through the weekend -- for the third time in a month -- to facilitate work on the two-lane corridor.The 55-hour closure began at 9 p.m. Friday and is scheduled to continue until 4 a.m. Monday, according to Caltrans. Motorists -- and residents along pockets of the Ortega -- are advised to prepare well in advance because access to large segments of the 17-mile artery will be inaccessible, with few exceptions."There will be no access from OC to Lake Elsinore and vice-versa,'' Caltrans District 8 spokeswoman Kim Cherry said. "There is no thru traffic, only escorted residents to and from designated places.''Residents who live