Barrier Armor Rating

One problem that I run into time and again with producing results for character-on-vehicle combat is coming up with a good BAR.  Support Vehicles get explicit BAR's, but BattleMech-grade armor is presumed to have a BAR of 10.  Given that Combat Vehicles have armor that behaves identically to BattleMech-grade armor in Total Warfare, it makes sense that Combat Vehicles also have a BAR of 10.

Here's the problem: During the infantry-on-vehicle combat example on page 212 of A Time of War, the Ranger being engaged by character is explicitly stated to have a BAR of 8.  I looked up the Ranger (page 26 of TRO:3085) and it is a standard Combat Vehicle.  This raises some problematic issues, specifically, that it implies BAR is not always 10 for Combat Vehicles.

Now, I understand, especially after my previous analyses, why an A Time of War GM would want to have a lower BAR for a hostile vehicle.  Vehicles are very hard to take down with man-portable weapons in this game.  That said, I worry about screwing up players' ability to analyze a tactical situation when we scramble those numbers beyond the rules.