Complex sentence: The Eagle Summit joined the Dodge Colt and Plymouth Colt in Chrysler's Mitsubishi Mirage clone club starting in 1989, coinciding with the release of the Mirage's third generation.
Split into simpler sentences: The Eagle Summit joined the Dodge Colt and Plymouth Colt starting in 1989, as part of Chrysler's effort in badge engineering the Mitsubishi Mirage. This coincided with the release of the Mirage's third generation.