240 is hard to get at that height and a big reason why you don't see many guys that big. I used to think exactly as you do here, lol! I'd plug in what I was doing, what it got me, then if I were to add such and such I'd make guess of where I'd be at.
I'd consider insulin to help you with this no idea what to tell you for gear. But do you mean 300mg or 3000mg of npp? Hard to tell these days, lol....