Been trying this for a few minutes and I can only get to a point where I grind the first, and then hit the 2nd, but when I hit it I land on my back wheel. If I were to try grinding the first in reverse from a krail and then lean forward/switch to the 2nd ledge, I still doubt it would be possible unfourtunately
![Tongue :P](//www.gtastunting.net/Smileys/gtas/tongue.gif)