The 12th Fleet: Starbase Valhalla

Launch shuttles, getting them to power down to avoid detection while I lure the warbirds away, the shuttles evacuating or restoring some of the Koyabashi Maru's power. When they're either evacuated or up and running, they'll meet me at a seperate location after losing the Klingons!

Well.. Assuming I dont get toasted beforehand

hmm clone Kirk and let him do it his way

I would go with a "Bluff" and reinforce it with the use of a telepathic crew member.

Coming into the system, I would order shields up, announce over open frequencies that we have come in response to a distress signal from the K.Maru who's mission was to aid a stranded Klingon freighter as part of a "good will" effort. After spotting the Klingon warbirds I would then hail them and ask if they are here to help the freighter, if so, we will tend to the K.Maru and respectfully remove ourselves from neutral space. During this time I would be preparing the transporters for a hasty transport of all possible crew to the most open and accessible area of the ship (Cargo bay) and would have my engineer waiting to hammer down on the controls.

At this point, I would signal the telepath to project the image of a Klingon supply freighter decloaking and warping out of the system to the Navigational officer of the Klingon vessel and await a response.

If the bluff didn't work, I would immediately transport as many crew members as possible off the stranded ship and do my best to turn tail and run with the survivors.

I would order Engineering to lock all transporters and prepare for a mass transport. Then, on my order, i would charge full impulse in between the Klingon ships and the Kobayashi Maru, with my dorsal side towards the Klingon's. While doing this, I would divert all available power to my dorsal shields, while dropping my ventral shields to allow access for transporters. Assuming I begin taking fire, I would return fire.