They may not have even made a second disk to a test floppy like that one since those components are pretty interchangeable between system versions (though I recommend using 6.0.8 for its printer drivers).

6.0.7 wasn't a roll-up release though, it was 6.0.7 with the bugs fixed. I think they used it for backwards compatibility because it's essentially the same thing as 6.0.8. There are two differences with 6.0.8 that I can name off the top of my head--the printer drivers are new and it will run on an LCII (possibly done only for the IIe Card startup floppy).