ORIGINAL: Countryboy
Sort of contradictory to what the manual states ...don't you think? However, I do agree the inlet should be on the o-ring side.
Apparently you have an older manual/turbine. I checked all my Jetcat manuals from 2008 back to 2004 & all have the same filter info. Below are scans from my 2004 manual. I don't have my older manuals, so I can't pinpoint what year the text & diagram changed.