The first step in breeding perfect Pokémon is to catch a whole bunch of Dittos at the Friend Safari in order to get many combinations of perfect IVs. I caught 15 of them, then proceeded to breed one of them that had perfect defense, special defense and speed with my female Jolly Heracross (which knew Rock Blast to boot). I know it's going to be hard to believe, but the second egg I hatched had all three. So I bred that one with a Ditto with perfect HP and attack, and made five eggs. One of them had a different combination of three 31s, so I took that one and bred it with a Ditto that also had three 31s, including two in different stats (meaning both parents had 31 in defense).
The second egg was a perfect Heracross.
Since you're probably thinking you misread that, I'll type it again:
THE SECOND EGG WAS A PERFECT HERACROSS.
Sure, that's without factoring in special attack, but still, it means that I went from zero to five 31s in NINE EGGS. Unfortunately my perfect Heracross is female, meaning I can't use it for Durant, but I have a male that has 31 in HP, defense, special defense and speed, so it's not too bad.
Next up is Durant, which is going to be a little more complicated, since a female with a DW ability only has a 60% chance of passing it down to its offspring. This means that any female with Swarm or Hustle, no matter how good its IVs are, is useless as a replacement mother.