Complex sentence: Following the conversion, the limousine's weight increased from 5215 to 7800 pounds, although it was not armor-plated, so the undercarriage and all suspension components were strengthened.
Split into simpler sentences: Following the conversion, the limousine's weight increased from 5215 to 7800 pounds. Although it was not armor-plated, the undercarriage and all suspension components were strengthened.