Just display the armor type and engine used by the vehicle one is sitting in or looking at down left in the vehicle HUD. Icons would be nice but if that is too much work just print the names of both in green letters below or above the armor/health display. That way you always know what your tank is made of even if you use a tank built by another player. The Grenadier skill Armor Detection should show engine and armor type as well. Well the engine type is of course discussable. The last point could make it possible to spot what kind of stuff the enemy team is using, which may be important information in future versions of the game featuring improved tech choices allowing for different strats.
Yeah, I agree with this, this is one of those things that can kinda polish this game. However, I disagree with this. Engine/armor should have at least some secrecy. With enough experience you can tell the armor/engine within 5 secs, but that's not easy in any way.