"Crikey they are hard...." what are you on, they are just a giant pancake.
Had two on my hotted up Austin, albiet many moons ago, and a lot smaller, atop twin 1inch & 3/4" SU's.
Come to think of it there was not much foam in each one. Wash in soapy warm water, smallest smidge of oil squeezed thru it, and your right to do another million miles. Cheaper than disposable filters.
