In my quest for more air, I came up with the following air cleaner solution:
First, special order K&N Filter E-2720. This is a 9" filter, and significantly larger than our old standby, E-1025. Then, order K&N X-Stream Filter Lid, 66-0901. Finally, buy 9" chrome filter base from local cheapo auto parts store (you'll probably have to buy the whole filter assembly, then discard the paper filter and the top). The photo above compares my old assembly with the new assembly. As you can see, mucho mas air. By the way, I don't think the standard 9" K&N X-stream complete assembly will work -- the filter element they supply with this kit is too tall and will not clear the hood scoop, at least on my car with a Shelby aluminum block and Shelby intake under a 1000 cmf Holley 4150 hp.
Then, get out your Sharpie and your Dremel tool. I installed the assembly, and then ran a bead of white grease around the outer rim of the filter lid. Lower the hood carefully, and the white grease will mark the clearance area to be removed. Carefully outline the grease mark with a Sharpie, clean it up, and dremel the right radius out with a cutting wheel. Then take that scrap piece and use it to mark a symetrical radius on the oposite side. I did this because I wanted the underside of the hood to look pretty, even though the marks from the grease showed that the filter lid was not actually centered in the existing hood opening.
This is what is looks like in place. Oh, and I took it out for a test drive -- the increase in breathing was immediatley and profoundly apparent -- AS IF I NEEDED MORE POWER! Wowzer. Also, I had to rejet my carb, since the increase in airflow created a slightly leaner condition. The air is also pretty chilly (and thus more dense) this time of year (45 degrees).
Hope this post is of some use to my fellow Kirkham owners, especially if you looking for a way to get more airflow than provided by the standard E-1025.