Freeman, the OP is attempting to dye only the figured maple top, and leave the rest un-colored, so we're trying to keep all color off the end grain area. As far as sealing before staining: generally I like to apply stain to bare wood, but there are no hard and fast rules. Sometimes you need to use some kind of sealer to get the results you are looking for. Really the only way to predict how something will look is to try it out on scraps. Keep written records of each experiment, or you will forget.