Rudy Peralta, a member of the City Council for three years and a Monterey Park resident for 25 years, will become mayor in ceremonies at 7:30 p.m. Monday in the council chambers at City Hall. He succeeds David Almada. G. Monty Manibog will take office as mayor pro tem. The offices of mayor and mayor pro tem are periodically rotated among council members. Peralta's installation will be followed by a reception, open to the public, at Luminarias Restaurant.