Okay basic physics/electrics.
The whole tower is metal and definitely grounded.
Should the current touch the tower, it's going straight to the ground.
The lines are isolated by glass / ceramic insulators so that they are far enough from the tower to prevent arcing even in wet conditions.
Should anything get between the line and the tower and provide an easier path to the tower, the electricity will take it.
There's no guarantee it will kill you (people have survived) but if you like living, don't.
The tower is grounded, and on a day-to-day basis, touching any part of the tower will not hurt you at all. It's when you get close to the lines and start introducing your mostly water-based limbs into their electric field.
If you stay as far away from the lines as you possibly can, you could probably get way up there and live. But if you mess up, if you slip, if a piece of gear or your arm swings the wrong way, odds are good you're getting zapped (and the resulting paralysis / shock will likely knock you OFF the tower, falling 50+ ft to the ground. If the electricity doesn't f*ck you up, the fall will.
If you value living, I'd say go climb a cell tower, transmission tower ... Nevermind, cell towers will fry your nuts. Climb a crane instead. None of those are wired with bare wires carrying 50,000 V.