The elusive 30 min 5K

Currently the only 5K I'm signed up for is the Heartbeat5000 5K, and it was my intention to make that my sub 30 5K.  I'm not exactly where I came up with the idea, but I'm afraid it's one of those foolish "I'm not a legitimate runner unless..." type goals that I really disagree with on principle, but still sort of want to achieve in reality.  I don't accept the method, but I can't always resist the madness.  

The goal "sub 30 5K" continues to seem thoroughly daunting.  My 5Ks thus far have been between 33 and 38 (not counting the one with Tony) and in no particular order.

The races where I got my fastest times were the Liz Logelin 5K, probably around 33:10, and the Jelly Belly 5K "virtual race" 33:24.  Both of these races were really informal and no official race times have been posted.  The first is based on my memory of the race clock.  The second is from my garmin.  

Clearing my previous "not even official" PRs by at least 3 mins would be pretty exceptional, and I'm not even sure it's possible.

What I've got going for me:
-I'm really in the best running shape of my life. This statement can in part be made because there was next to no running for the first 25 years.
-I've hit the necessary 9:40 pace on shorter 1ish mile runs.
-I will do everything I can do sleep right, eat right, drink right the days (and weeks to some extent) before the race.

What's not in my favor.
-Despite some nice fast short runs, I'm still significantly slower on similar distance type runs - around a minute/mile.  
-My training must include long distances (hello marathon!) right now and I can't strictly focus on speed work

All that said, I would still be really happy if I came in under 33 mins - it's an official PR!  How could I not be?