I think that kit will probably include 31mm festoon bulbs/lamps. They can be made to fit, but you will have to distort the holder and include a bit of cussing in the process. IMHO it is better to order the 28mm festoons and avoid the headache. The OEM festoons on the CX 9 are 31mm, but that is including the little teats on either end of the bulb/lamp. File those teats off and you've got a 28mm bulb/lamp. That little teat has no value for retention or anything else that I can see. You can likely do just as well on E-Bay (I'd highly recommend the 28mm festoons) and come up with a few spare bulbs/lamps in the process. Your call.
I got mine at www.superbrightleds.com and they fit perfectly. about a 10 minute job to replace them all.
Thank you ArkanDan and Bob2525 for the info. I also want to do this in my 95 f150, I think it would look killer.