It'll be sweet, but lots of figuring. So in a rear pull the aluminum hawse plug and tube would need to handle the force of the pull? I guess every bend needs to be able to handle this force also, thus the need for the heavy wall tubing. I'd be tempted to use snatch block type pulleys at every bend and use tubing just to protect it. Are you going to center the thimble in the front? If so those will be some sharp angles.