Small engine clutch
 

Hello, I have a 9 hp Honda motor that I am trying to fit to my go kart. The motor needs a new set of clutches. I believe called a torque converter? Anyway, I was wondering if there were any difference between buying the drive clutch and the driven clutch separate or buying the together. The reason I ask is because separate, they are about $130 each but if you buy them together, it is $180.
Here are links to the separate clutches-
http://www.ebay.com/itm/1-40-SERIES-...#ht_1753wt_922

http://www.ebay.com/itm/Comet-Torque...#ht_3440wt_689

here is a link to The two together-
http://www.ebay.com/itm/1-GO-KART-TO...#ht_2073wt_922

Is there any difference between them? Also, if I buy the two together, do I have to keep on the mounting bracket like shown in the picture?