1999 GMC C6500 Topkick Engine: 7.4L V8; 8 Way Female Connector w/Leads;. 2000 GMC C6500 Topkick Engine: 7.4L V8; 8 Way Female Connector w/Leads;. Parking Brake Switch Connector. Professional appearance - this electrical pigtail is designed for a clean, professional look when installed.