I'm always a bit apprehensive about sharing home brew tools for personal consumption, but here are a few things I should mention just as FYI if you are not as familiar with Excel or possibly importing differently into other apps.
In the calc tab, if you hover over a (red) input cell that shows a little red triangle in the corner signifying a comment, it reveals some information related to that parameter to help you along.
In the fig-13 tab (which is named to coincide with plot recreation of SIC Figure 13) I directly import the Trimble parameters from calc tab (blue font). I also allow input any arbitrary parameters I call Engine X in order to show how it compares against the 4 constraint curves. You can turn this on & off using the plot filter button