That’s a scary looking lift. I did not learn much in HS geometry but that does not look right . The last 61 I received from Japan had a similar skywalker lift and it rode like crap. Plus there was no adjustments for the pinion angle so I had a ton of pinion gear slop as well as bad u-joints. Swapped in a new yoke, rear diff and and an OME lift and all is good. Not sure what the folks over there are thinking when they do this to their trucks. Here’s a before and after of the referenced truck.