Just curious but I have to ask. Why would you want to use a "dye" as opposed to a stain, oil finish or polyurethane. Ritz dye is generally sold as a cloth or material dye and IMO would produce results similar to ink. Before you hit the stock with a whole bunch of that I'd suggest trying it on something for a test.
Also since wood almost always darkens when you add any kind of liquid start with something lighter than you think you might want. You can always make wood darker but it is very difficult to make it lighter. If you start too dark you may end up with something nearly black.