Complex sentence: In 1963, General Motors' Chevrolet division produced 57 full-size Impala coupes equipped with option package RPOZ-11, which added $1237.40 to the vehicle base price.
Split into simpler sentences: In 1963, General Motors Chevrolet Division constructed 57 Impalas equipped with option package RPOZ-11. The RPOZ-11 option package added $1237.40 to the vehicle base price.