This guide has been extremely useful to me and I sincerely hope you continue to update it. The performance point feature is quite nifty as well.
That said, I've found myself adding quite a few other spreadsheets from other sources and combining them to work together for my needs. I think perhaps they could be useful to others as well.
For example, I've added the used car list on a separate sheet, and added a wishlist column to the regular car list. I've added some conditional formatting which highlights any cars on the used car list I am looking for, and highlights any cars that can be won in a different color so I know not to buy them unless I need it now or plan on having two.
I've also added the paint color database, as I find myself referring to that sometimes.
Finally, something that probably isn't that useful but could be interesting, using
Parnelli's racing guide as a reference, I've added a sheet where you keep track of what power and weight combinations result in close, exciting races. By calculating a best fit curve, it allows you to approximate the HP needed to have the same level of racing. Then, on the main car list, it can figure out which cars are capable of getting to that level through tuning or detuning, based on the maximum ballast you want to add and the maximum power limiting you are willing to do.
The matrix is a great resource but I think it could be more complete with a few additions so that no one has to look to other files for information. If you add the used car list, it would require updating more often than the rest of the sheet, but it wouldn't be too hard for users of the matrix to add that themselves from the updated files in that thread.
If you would like me to send you what I have so you can see all this nonsense for yourself, feel free to ask. I think it could be helpful for some people so I would like to share it.
