Looks like you may need to get a piece of threaded rod, or a long bolt to secure the new filter down when you get it... I do not believe the K&N comes with anything like that. Personally I prefer threaded rod long enough to go through that way I can jam nut the filter down to keep it from vibrating loose while riding (that happened on a trail once... We had to limp the quad back to the trailhead to get another nut). Since then we have used a jam nut (a lock nut would work too) to hold the filter in place.
Just something to consider getting while you are waiting for your new filter to arrive.
Also ours came with the end cap that holds the filter in place. If by some chance yours does not come with that get a hold of me, and I will get one for you. Although I would be pretty sure you would get a new one with your K&N.
Also in the mean time you really should carefully clean out that airbox and carb to keep contaminants from sucking in... That pretty new filter will be useless if you already have dirt behind it.