General Motors Corp is scaling down plans to build cars in Russia with AO AvtoVAZ, signalling continued hesitation of foreign manufacturers to invest there, sources told today. The project was to invest $500m-$600m to produce two types of vehicles under the US automaker's Chevrolet brand: one based on a mid-sized Astra from GM's Adam Opel AG; another derived from AvtoVAZ's new small sports-utility vehicle, currently made in limited volumes as Lada Niva 2123.