Originally Posted by Kaben

I have a set of Look Keo 2 Max pedals that were adapted by Dolan, they bolted an extra carrier to the back. For double straps the front strap is still done with zip ties. Hopefully these pics make it easier to see. I would imagine it would be easy enough to make a looped bit of steel and bolt it to the pedal body.
Having the rear loop at the back of the pedal ensure the strap stays mid foot rather than just being over the toe area like the fabric straps that attach at the axle.