Resolutation Independent GUITexture placement

I am trying to make an iPhone game with a thumb joystick. I would like my unity editor to emulator the correct iphone resolution as much as possible. I would like the thumb joystick guitexture to always be at the lower left hand side of the screen. This is how I go about doing that.

	joystick.pixelInset.x = -(Screen.width * .70);
	joystick.pixelInset.y = -(Screen.height * .40);

However when I change the resolution, the joystick doesn’t appear to be in the lower left corner.
What is the best way to position a guitexture object in roughly the same position regardless of the resolution?

Set all pixel inset values to 0, and use transform.position instead. Set the size with the scale.

–Eric