I've been using aniline dyes for over 10 years.....I never quite warmed up to the concept of putting down any sort of basecoat, be it shellac, sealer or anything else, before the dye process was completed! Surely someone out there could find flaws in other methods, but aren't dyes supposed to be applied to wood?....afterall, you objective is to dye the wood, not the sealer...it is no wonder streaking takes place.
Here is a pic of a tele I built a few years back using water based aniline dye.....
http://www.fenderforum.com/userphotos/index.html?recid=2958
http://www.fenderforum.com/userphotos/index.html?recid=2973
No sealer was used until the dye job was completed....
If I were finishing this guitar, I'd sand it down and skip the lacquer or sealer until I've dyed the top. Use CA as a grain filler. Be sure to dampen the wood before you apply the dye, this will help prevent streaking.
It is like nearly anything else, ask 5 guys how to do something, and you'll get 5 different answers. This process works for me, it may work for you.