The K&N web site recommends part number 56-9237 which is a frustum with dimensions 5 7/8 ->3 1/2 x2 11/16" thick. A thread in the archives suggested their custom filter # 56-9247 which requires drilling holes for the mounting bolts and the air passages. Any thoughts on the relative advantages or fitting issues? Thanks, Peter Schauss 1963 BJ7 1980 MGB