I used Cu-Ni (copper Nickel) on mine after multiple leaks with the ones I ordered from Classic Parts. Here is the post That shows the results. https://www.stovebolt.com/ubbthread...s-filter-with-hard-line.html#Post1437615

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
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