In acknowledgement that Germany is simply becoming too expensive as a manufacturing base, the Alcatel SEL AG arm of Alcatel NV is to sell a plant in Landshut that employs 608 people and another in Stuttgart that employs 53, as part of its program to reduce its workforce to 13,700 by year-end from 16,000 at the end of 1996. It had planned to cut only 1,500 jobs this year.