most guys just use an ink pen to stick thru the hole and do it that way. when i had mine i made an extension which was just a bent piece of stainless metal that you could reach with a finger underneath the grille.
The Street Scene grilles come with a cable and T Handle that attach to the stiock hood latch. When you pop the hood from inside it sits in the space between the hood and bumper. Just pull on it and voila'!
But I always carry a screwdriver in my truck just in case that cable decides not to work.
Just take a piece of sturdy cable, and a couple "eyelet" screws. Connect it to the existing lever, then feed it down to the bumper area, then make a circle out of it. Or, you can buy a t-handle one on ebay pretty cheap.