Are you sure the CA160 is the right filter for a 4bbl 273, 1966? I checked out fram's site and even on there it lists the 162 as the right filter for a 4bbl and the 160 is for a 273 2bbl in 1966. The only difference is the 162 is 3.27 in tall and the 160 is 2.78 in tall. I dont think half an inch is a huge deal but I just want to get the right size if I'm going to drop some money on a KnN.
The other years, '65 and '64 273 4bbl seem to use the same filter as the 2bbl 273 in '66. Isnt the 2bbl 273 air cleaner the same as the 4bbl but just has a 2bbl bottom plate?