At this point riveting is second nature. Lay the skins on, strap them down. Go inside and mark there the bulkheads hit the skins. Take the skins off and pre drill them. Deburr, and restrap to the fuse. Drill through the skins to the bulkheads. Take apart, debur, dimple, and rivet.
Here is the porcupine.
Bucking inside does require some finagling. Bring everything you need cause getting in and out is no small feet.
And wallah, another riveting session completed.