Yes, looking to add a dash switch to open the glass hatch. Was hoping I wouldn't have to run a wire all the way from the trunk to the dash, but rather just find it under the dash somewhere. Maybe it's easier, as you suggest, to hide it under the bumper or something. (Pretty hard on any switch to be out in the elements though.)
Also, you say Grn/Blk but from the diagram, that appears to be related to the tamper switch, not the unlock. Don't I want the Lt Grn wire?