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That depends on intent - real time used really long drain back line from the valvecover and port to help the open filter system, these were also hand built and extremely tight engines with little blowby.
For a standard engine I would use the PCV port hose or a clamp on an fitting that could screw into the can to make that line as short as possible, also run the block breather line to the second entry and use the top mounted return line to connect your intake, this will provide ample vacuum so as not to lose power while still separating the liquid bits, from the vapor, helping.
The engine this was build fot use and AN fitting but we found we could dump the PCV system into the exhaust and not worry about overflow during endurance racing.
Here is a mockup I just sent another member on another TSX