Installing rear wheel
How tight do I want the rear wheel/hub nuts? I've been going as tight as possible with overtly straining myself. Should I go tighter and just crank em down for safety or maybe I'm already going too tight? Ahhh I'm not sure and on one hand I don't want to screw my frame but I also would like to stay safe while riding. Having my rear wheel come forward and loosing chain doesn't seem appealing to me.
Making a kilometer blurry
It doesn't take much. I think I've seen 14 ft-lbs. So, with a normall 17mm wrench length, you'd probably be pushing with ~35 lbs of force or so? A competition tandem will require more, but you're not putting out 3400 Watts
Am assuming you are talking about closing the skewer?
You are being paranoid, whatever u can do with one hand is fine.
Yeah, I never use two hands or leverage on anything. I just go has hard as I can with one hand without hurting myself. I am being paranoid...it's something I'm trying to get rid of.