That red line represents Chaney's position. He is somewhere along that line of sight. At each point along that line it also represents his distance from the side of the limo which increases the farther back along the los that he is positioned. That tells us how close his handle bar is from touching the limo. The bike is 38 inches wide so it extends out 17 inches to each side of that red line. At the position near JFK there is less than 17 inches between the line and the limo so his handle bars would hit the limo. He need at least 10 inches clearance between his bike and the limo. He would not fit near JFK, only farther back near the rear bumper.
Regarding shadows, we know the azimuth and we know where the bikes were pointed between 200 and 270. It is simply a fact that the angle of those shadows at Z 255 point more than 60 degrees to the rear at about 140 degrees. The evidence, the azimuth and the direction those bikes were facing, is indisputable. Every other photo of that day verifies the azimuth. Of course you see 90 because of PERSPECTIVE. If you see 90 you can be sure it is other than that because perspective does not allow you to take an accurate measurement. The closer to the ground you are the more angles move towards a horizontal position. That is why it looks closer to 90.
I mentioned 2 ways you could test your theories that only take a couple of minutes. You should test your observations. You can just take the map and draw a line for the azimuth and another for the direction of the bike. You will see the shadow does not extend out at 90 degrees it is 140! That is another very simple way to test it.
