Chrysler Corp. said Monday it will invest $1.2 billion in a new Jeep assembly plant and existing facilities in Toledo, Ohio, ending months of speculation about the future of Jeep production there. Under a deal struck with state and local officials, Chrysler said it will build a new, 1.1 million-square-foot assembly plant adjacent to its existing Stickney Avenue plant on Toledos north side. Construction of the $600 million plant is scheduled to start in 1998, with assembly of Jeep Cherokee and Wrangler sport utility vehicles starting there in 2001. Chrysler will spend another $600 million to refurbish an existing 290,000-square-foot building on the Stickney site.