I would leave out the Wheat DME. Cooper's kits are best if you don't get carried away and add more than 2#s of extra too it. I would add the 2# of LME, and all of the 1/2# of Dextrose saving back just enough to bottle it with.
As I understand it, the cloudiness of Wheat Beers is due to the yeast thats used, so I'd expect if you're using the Cooper's yeast with the IPA kit it will clear up nicely even if you use the Wheat DME.
I've made the Cooper's IPA kit a few times, if you want to know the truth about it - the best way to make it is use 2 Cans of the IPA kit and add nothing else. Its really really good that way - I've only had one IPA that I enjoyed more.