Yeah, it's nice to know, isn't it? I also think that these bars are surely made on more than one jig, so there may be some variation.
I have a square area, but you can use a strong cardboard box, cut the top & 2 sides so you have a corner. Turn the bar upside down, push the center stem area against one wall, touch the grip area to the other, put a phone book on the other grip area, look down & line the center area up with one card board wall & you're in business. A tri square, or something like it will help with rise.
The Wald 828 measures a 1/16" under as the center is 7/8" rather than 1", but I didn't note it in my diagram, it was so close overall.