I can pretty much get the veneer on now, doing it just as you say. But I am still fighting the finish. Current method is to use sanding sealer, then spray on lacquer with HVLP sprayer, sanding between every two coats. Getting the right ratio of thinner to lacquer is so far sheer guess work. Then finally polish using an orbital car polisher and Griot's different levels of machine polish. My finished product looks OK, but not like the dash on a Rolls Royce, which is what I aspire to. There are still small errors, both in the wood and in the lacquer, that show on close examination. I have been practising by refinishing the bases of my Bottlehead gear (you can sand away like mad, which you cannot do on the veneer), and am now making a small pair of veneered speakers on which to experiment further. Have also ordered a book from the library on refinishing, so eventually I should be able to do it.
What kind of lacquer are you using and what are you thinning with? If you find yourself thinning quite a lot try moving up to a bigger nozzle on your HVLP. Are you using a turbine or compressor driven system? Nothing beats practice. And a bright halogen shoplight illuminating the work from the side can show imperfections and dust on your work that are otherwise invisible to the hands and eyes. Buy some good cabinet grade plywood to practice on and cut it into several chunks. Sand it with a random orbit 120-180-possibly 240 but no higher. Tack it off good, apply thinned vinyl sealer, scuff sand, and then start lacquering. If your shop temperature is reasonably close to 70 F, you should be able to sand and recoat within an hour or two. Let the final coat harden 24 hours or more before you try polishing. Unless you are sure of what you are doing it is a good idea to do your between-coat sandings by hand. 3M makes some foam rubber sanding pads that are fantastic for this step. I use the Superfine. They are about 3/16" thick and rectangular, grey in color with red lettering on the back. Their rectangular shape will just fit on an old-fashioned quarter sheet sander, which is what I use to speed things up. 3M scotch-bright pads can also be used, the gray ones are about right.
Gloss shows everything, and like a previous poster said, preparation is key. If there is a scratch, swirl, or dust spec in the sprayed finish, polishing will not make it go away.