I read this post last night. Today I went out for a little offroad trip. For the first time ever, I left my cell phone at home. About ten miles out, I pulled off the trail to take a break. When I got bact into my truck, it would not start. So after several hours of doing wiring 101 for my life, I discovered that you can pull the relay and jump the red to purple, and wala the CUCV runs. SO now I am looking for the correct part. According to the pictures at Kragen and NAPA the AC40 has 5 pins. The AC delco factoy part # has four, like my truck. The AC40 is about half the price. Can I get away with the AC40???