I also had an issue buying the proper filter and gasket for my ‘59 235. I saved the carton top of the one that fit for future reference.
NAPA part# FIL-2006 and WIX 51006.
I understand WIX no longer makes these for NAPA, so I don’t know if the replacements are the same. I screen printed the specs on the WIX filter that shows the gasket size. Mine came with two gaskets, one that fit and obviously one that didn’t.
At any rate, it may give you another option.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum