I am guessing the only difference between running the PFT course wherever you and your OSO do it and running it at Quantico is the adrenile of that initial PFT is probably going to have you so pumped you will run your a** off.
It is all mental. I just finally decided to apply for OCC 191 Oct. 10 and am already looking at a 260 or better probably in just the PTing I have been doing for a month, and I don't have some great genetic potential or anything. So if you have been PTing for a while your lungs and legs are probably conditioned to handle a good pace, especially if you are regarly running twice the distance at the same pace as you do a PFT.
If you don't feel like you are going to collapse and pass out in a pile of your own vomit when you cross that finish line then you are not running fast enough.
S/F