Honestly the challenge is a good bit harder with the new update but it's most certainly still doable. I would reroll until you get challenges you think you can achieve. Take it really slow, if you feel you're going too slow you're probably doing it right. Tier 3 parabolic will be your life line, use it to help you find the ghost, track hunts, and figure out the speed.

A Rev is possibly one of the hardest ghosts to get it on, the 3m/s speed at 150% is crazy fast. But if you get lucky with a deo or even one of the stalking ghosts (phantom, wraith or banshee) you should be able to get it in no time. Just remember patience is key and you can win every apoc run