Just picked this one up today with a final score of 114,375 when the achievement popped, just under 11 minutes play time. Here are my notes:
1. Hardest part of the Achievement is unlocking E-4
. And yes, while the level is easiest to get a gold star on by jumping in a ghost and shooting everything, this wasn't too hard.
2. Don't upgrade anything
. Turns out the Plasma Repeater and Plasma Pistol it gives you to start the level are a good combination to use. I would advise trading out your Armor Ability for the Active Camo that is near the beginning (to the left of where you start). Other than that, Elites will be good to give you more plasma grenades, and plasma pistols are abundant. This has a secondary bonus of you not having to press "E" accidentally and climbing in a turret / vehicle.
3. Remember the overcharge on the Plasma Pistol
. If you click both mouse buttons simultaneously, you can overcharge your Plasma Pistol. Unlike some other Halo games, this DOES NOT drain your energy. I used this more than I thought. Gold Elites can be brought down with two overcharged shots. Ghosts can be brought down with three. Wraiths are in that range too. The overcharged shot will cause vehicles / turrets to stop functioning (and running you over) for a time to switch targets or fire off more shots.
4. Save Grenades for disabled vehicles
. They are a heck of a lot easier to blow up when they aren't sliding away from your thrown grenades.
And just like that, the level is over, and you got another 10G!