Yeah, I'd like to know too.
Dyes tend to creep into the wood and on the side view, you can see that, usually. Perhaps if the sides were sealed 1st, you wouldn't have this problem.
Easy... yep, I sealed the sides and back with shellac then final sanded the top to make sure the top had no shellac. Then I dyed the top with denatured alcohol and Transtint dye. (I don't do water based dyes when there is bare wood involved.) and scraped and sanded the eage to break the sharp edge and expose a little more maple. Spray another coat of shellac over the whole thing again to seal in the top. After that is dry I mask off the Maple binding with 3M Pinstriping tape (Vinyl not Crepe) and masked off the top then I was able to shoot a toner coat over the back and sides. The shellac sealer makes for nice crisp tape lines and no bleed.