Johnny,
What is your reasoning behind wanting to take 6-OXO during the cycle?
Taking 6-OXO (or any other product designed for raising your NATURAL production) during the cycle is pointless. You'd be throwing your money out the window by doing that. None of those products will prevent your HPTA from becoming suppressed when you're on M1T. M1T shuts down the HPTA very quickly and severely. You need to save it for after the cycle.
The length of PCT depends on how long your cycle was and how you specifically respond. Everyone is different, and some people can get away with shorter PCT than others. I'd err on longer PCT vs short. The last M1T cycle I did was eight weeks @ 10mg/day. I then ran 6-OXO for 20 days @ 600mg/day (two bottles). From there I went on Gaspari Novedex XT, and did 3 caps each night (180mg/day, --max dosing is 240mg/day) for 20 days (1 bottle).
I felt I recovered very well using this protocol. I kept my strength gains post M1T, only lost a couple pounds (which was likely water from M1T), and even after I stopped the PCT, my gains continued.