Thanks for all the comments!
Fresh coat of olive drab on the tank. There's a slight shade difference between the turret and hull; the turret has a green primer under the OD and the hull is in black primer. It makes it appear as if the turret is a new addition to the older hull:



Now to paint the tracks, add the "glass" parts to the turret vision ports and sensors, maybe add one or both of the spare fuel tanks from the "Apocalypse" tank and start weathering.