There's a trick to doing the longer ropes. You can do the 100" ropes in sections of 3, which keeps the thread cleaner and reduces fraying. Do the first 32 inches normally, then splice in a new thread through the last 5 pearls. You'll want the last 5 pearls drilled slightly larger so you can use two threads, then keep going on the new thread for another 32", do another splice through 5 pearls, then do the last 32" and finish the necklace. Done right, it is nearly impossible to determine where the splices are.