Well, it wasn't easy...but I was fairly prepared for it.
I used Amuro with the Unicorn Gundam.
Ace Killer, Ace Pilot, Serene Mind. The Gundam had Minosky Drive, Hard Hit and Armor Gain.
Frontal was my partner.
I used the hit&run tactics to build up my hit count. If I had to face an ace, I opened with an SP attack and quickly finished off the ace while in Destroy Mode.
I tried to stay in Destroy Mode as much as possible, as it made it easy to wipe out fields quickly so I could move to the next.
I took a few inconsequential fields to build up my kills to 300-400, then took out the factory. Zipped around picking off an ace when possible, and built my kills up to 700. Then I took out the factory, took out the rest of the fields. The boss (Lunamarie) showed up by this time, but the first time I tried taking her out, the other aces from the field showed up AS WELL AS tweedle-dum and tweedle-dee. So I reloaded and picked off the remaining aces before going into the base. The SP+Destroy Mode picked off the two Musha suits, and I admit I got lucky because one dropped a Haro-ball so I was able to SP the Knight Gundam into submission without it getting a hit in edgewise.