General Motors said it will offer cash...

General Motors said it will offer cash rebates to buyers of some 1988-model cars and 1987 trucks. Buyers of 1988 Chevy Camaro and Celebrity models can choose either a $600 cash rebate or free air conditioning, while buyers of certain 1988 Pontiacs can receive a $500 rebate or air conditioning. Industry analysts say the rebates appear designed to keep GM sales, which have been dropping, from falling even further as the aftershocks of the Oct. 19 stock market crash are felt. The rebate program, which takes effect immediately, will last through the middle or end of January, depending on the car.