The 9" is a tad long but will fit.
In the picture below the nose of the filter is up against the radiator cross support. I suppose I could pull it back a little if the tube assembly was shorter but it works. I'm going to have to get creative for an air divider.
It's about 4.5" wide at the base, can't recall the part number, probably have it in my file somewhere. You could go with a wider filter that is shorter and have the same surface area. I wanted a narrow base to allow some room for the snow system tank.
This is the one I have, though I got it from a local supplier where I got the intake pieces from.
http://store.summitracing.com/partd...744162+4294791583+4294790256+115&autoview=sku