Most efficient way to fill and finish basswood?

I'm at some point going to be starting a build of a rocket to be covered with Accur8 skins. John recommends the wood parts be glossied up to adhere properly to the vinyl. The wood bits will be basswood.

I haven't worked with basswood as a fin material much (at all?) What is the most efficient way to fill and smooth it? Do you treat it the same as balsa? It feels like the grain is much denser, and maybe shouldn't require as much effort as balsa, but I don't know what that translates into. Is a heavy coat of filler/primer enough, or would a more standard CWF application followed by filler/primer be more appropriate.

I was also wondering if it would work to apply clearcoat such as Future directly over the sanded filler/primer, enabling me to skip the paint phase....

It doesnt require as much effort as balsa usually. My preferred sealer is Deft Lacquer Sanding Sealer, its brushable and dries quick, on top of that I have yet to find incompatible color/primer coats in the normal hobby paint types ( Testors, Tamiya, Rusto, Krylon).

Sand and prime, sand and prime, buddy. You need nothing else for any type of wood to get a good finish if you are diligent with the sanding and priming.

Sand and prime

Sand and prime...

Basswood is a pleasure to work with. It is about 1/3 heavier then the same thickness of Balsa but the tight grain and harder sap wood make filling easy.

As with all my models these days I DO NOT use any kind of wood filler, sanding sealer or other waste of time and Money fillers. a coat or two of cheap sandable auto primer is all thats needed. If I've already mounted the fins on the body I'll use my standard 3 wet coat of primer method, let dry overnight and sand with 220 -360 grit DRY papers the next day. Smooth as a babies butt! Generally it's the body tube seams that require an additional coat or two.