hi Joe, you're right the lock position is important. I've witnessed many tail "wraps" which IMO are still a good sign, so be positive. But the telltale sign is seeing the female clearly overlapping the male and best indication is seeing the male's tail standing straight. The latter is not necessary, again just a strong indication they've docked. Couple pics from my breeding season below illustrate some successful locks: (hope this helps, good luck!)