got my head above blood gultch today. If you get lucky you can make it up. This is what you need to do:
Get a tank and a jeep to blue base. On the left side cliff wall(left if you face red base)There are 2 areas you mite be able to make it up. The 1st is that dirt path near the arch, the second is a more hill shaped cliff to the left of it. you drive the jeep up the cliff or jump(if you take the dirt path you make a small jump before you hit the wall) get the tank to shoot you, you go flying if you do it right, and I have been close many times to getting on top. But once I got my head higher then the level, it looks like the area above sidewinder.
oh almost forgot, you need to have 400% health or you die when the tank shoots you