Also just wanted to add got my carb kits from a dealer in Canada NOS OEM Kawasaki parts. I have learned my lesson on the cheap eBay carb kits :P not for motorcycles but for other things I have worked on.
Z1Enterprises.com sells carb holders. That should be your first priority because if the old ones are cracked you can easily hole a piston running the bike. Next, the carb kits you bought on eBay that come from Japan are sold by a Japanese seller and are not made in Japan.... somewhere else in the 3rd world and not great quality; in fact poor quality.