Hi,
I know this is old but maybe you'll see it. I tried putting a Firestone liquid post on the 3/8 flare but it just doesn't fit. Subsequent research shows a 3/8 MFL to be 9/16-18 and a Firestone liquid post to be 5/8-18 or 3/4-18 (John Wood 85 older models). But a Firestone gas post is...