82' 75 hp Johnson shift rod length

[mich-fish]

Just checking out a new to me engine. I removed the lower unit to replace the impeller and saw online about adjusting the shift rod to a certain measurement. Is the measurement in F/N/R? and what is the correct measurement? I also found that the lower unit oil was milky. I drained the fluid and performed a vacuum test and a pressure test and both tests passed. Seals on fill plug and level plug are good. Any ideas? (thought about running it for a month or 2 and rechecking) Thanks in advance.