It seems like someone at PGI misread this line:
"The Capellan Confederation expanded the utility of the Guardian even more with the introduction of Stealth Armor.[3]"
And then they bundled it as part of the basic guardian ECM, which has an extremely low weight/crit slot penalty. So... simply put - do as many others have suggested before. Remove the stealth armor portion/null signature portion and add it as a separate component. This would balance it out by removing critical spaces and forcing people who pick this as an option to be far more judicious (thus removing armament/tools) in the application of their chosen mech build(s).
http://www.sarna.net...i/Stealth_Armor
"BattleMech Stealth Armor provides as much protection as standard armor. It takes up two critical slots in each arm, leg, and side torso. To work, it also requires the 'Mech to carry a Guardian ECM Suite.
The system can be activated or deactivated in the End Phase of any turn. When active the system builds up 10 heat points, and is affected as if it is in range of an enemy ECM Suite. Any unit attacking a BattleMech with active Stealth Armor gets a +1 hit penalty at medium range and a +2 hit penalty at long range. The Stealth Armored BattleMech cannot be a secondary target while the system is active."
So in game terms it would function as an upgrade only available on ECM equipped mechs.
It would build up heat when turned on.
It would take up 2 critical slots in each arm, leg, and side torso. This would significantly limit most of the mechs which can carry it.
WHY REINVENT THE WHEEL?
Edited by Gevurah, 26 February 2013 - 11:02 AM.