Looking at Ramchargers web site, there is a fan #674001 $79.99, and a plug in harness #674002 $22.95. There is also a fan w/harness #674003 $139.99. Question-----can anyone tell me if the harness included with #674003 is the same as #674002? The price would indicate that there is more to the harness included in #674003. Thanks, Brian