You're right Ostketten... the 3v laser diodes [$6 on ebay] are just a drop in mod for the HL tanks. I have mine wired up, but haven't installed it in the mantlet yet and it works great. The stock turret machine gun LED in the HL tanks has about 2.5v going to them and it powers the laser diode just fine. I snipped the wires to the MG LED and just soldered the laser in it's place. Now the transmitter MG button controls the laser - much like the Creeping Death version. I hope to get it installed in the next few days and will pass along my convergence point experiences