Battle Technology isn't an official source.
Q: Is the Huntress BattleMech showcased in the old BattleTechnology still considered cannon? Are there any ground rules for making TankMechs? If not, can we see some made in the next incarnation of BMR or MaxTech?A: Any unit that appeared in that magazine can be considered a part of the BattleTech universe, even if it is simply a unique prototype somewhere. However, they are not legal for tournament play. As for TankMechs, there are no rules covering that and I don't have any plans for a new rulebook in the near future, so we'll just have to wait and see. ;-)