No guys I was not aware of that. When I was searching this site about taking these measurements I read some debate about the accuracy of the Liskey diagram but not that specifically. That is definitely something I will revisit.
I did these measurements back in July and was going off memory so I went out to the shop and found the notepad I was recording them on. I do see now that all three cars measured 7 to 7 1/4" at the spring bracket which Liskey has at 6.5", and the rail/floor support intersection were at all around 6 7/8" to 7 1/8" which Liskey has at 6". Curiously the crossmember area measured around 13" just as Liskey does.
Since all 3 cars were consistent I assumed all was ok, and I guess still may be. But next step will be to remeasure using the correct starting points.
Thanks for the help.