Pursuing the Ark. Any thoughts?

getting that last chest on the level is a real brainteaser. Your jumping from across the tops of moing trucks. Eventually, after knocking off all the henchmen, you drive the truck ahead to the next group. The second time you do this, a little pickup truck appears with the last chest. Problem is, its only there for a few seconds and when you try to jump to it, there's a constant risk of hitting the ground and dying. If even a few seconds are wasted getting on, by the time you get to it, the chest disappears. Anyone have tips or cheats to overcome this>