The -10
If I am not mistaken, you are advised to start the empennage first, followed by the -10 tailcone. This sequence is just as it is recommended on the other RV models, albeit the other ones don't have a dedicated (separate) tailcone like the -10 does.
While I suppose you could jump to another part first, I think the experience learned on the empennage/tailcone will work wonders for you when going on to the next sections.
Good luck.