You will be a LOT better off than the dude in the video in that I presume that you will place the lift so that the vehicle is perpendicular (rather than in line) with the trusses, so that you will be placing the vehicle at the high part of the scissor trusses. When he does all this work the ends of his vehicle on the lift will still be really close to the ends of the trusses.
I noticed that his scissor trusses are made from 2x6s instead of 2x4s...
