So our guest book is a wooden frame with a plexiglass front where guests write on little wooden hearts and drop them down in like plinko. I'm trying to decide what type of pen would be best and thought you all might have some experience here. I am leaning toward sharpie pens and will likely just test them out on one but I don't want to mess up too many of course. Whatever we use has to write smoothly on the wood, not bleed, and absolutely has to be acid free/archival since clearly we want this to last. Thanks!!