Highly recommend to download the internal mod https://flightsim.to/file/36006/pelican-improvement-mod as well which you can have an enabled machine gun. And the author will have John and Cortana on board later I think...

In the Halo TV series, John, the #117 Spartan 2 Chief and his Silver team fly with a Pelican #325 all the time.

The Pelican in the TV series has a D-77 cockpit, but with D-79 wings and engines. I guess it is the D-78. There is no photo of the Pelican D-78 what so ever.

The MSFS2020 stock Pelican is D-77, so what I did is to make it as close to the D-78 as possible from the livery level.

I noticed that the #325 Pelican in the TV is always pretty much intact, there is not even a scratch on it which I can identify from my TV screen (May be John can always clean the ship with the power of the artifact, or my TV has too less resolution lol), so I keep it with very light washouts.  Enjoy it!