Pinion angle and diff centering

Here's a good utube vid on this: "How to properly setup & measure your pinion angle on your muscle car" though I thought that when you get that right that you lower the pinion a bit more to compensate for pinion rise on acceleration but this might just only be on a muscle/drag car but not on a DD. I'm learning too. EDIT I see that the gauge is hitting the ujoint cap strap in the one pic, I'm assuming that that was only to get a pic of the gauge setting on the bottom of the ujoint not to get an actual measurement. I would not go by the oil pan rail & the next pic after that I would use a round magnet to get to the actual ujoint flat cap itself. Just me I think I would get the angles correct then weld the perches at that point rather than the MP 5 degree setting (how often would you be swapping the rear end into another car)