While simply nailing or screwing objects into place works, this crude method scars the boat and makes revarnishing difficult. Thus we’ve developed a number of different methods of artifact attachment over the years. My favorite features tiny brads or small brass finishing nails.
First, we clip off the heads and pre-drill tiny holes to the correct depth in the wooden artifact to accept those ends. Only slight tapping with a small hammer is required. Then we place the item on the bulkhead exactly where we want it, and gently press to mark where to again pre-drill. Done right, these items 1) easily pull off the bulkhead, 2) never fall off, and 3) are easily mounted or remounted, perhaps with a dab of white glue on the brads. The tiny microholes in the bulkheads can ultimately be varnished over to become nearly invisible. We also use string and thread in creative ways, along with double-sided tape and clear silicone sealant.
We’ve never found anything worth displaying that we couldn’t artfully attach — even our famous (and much-admired) Tongan war club.