HV300 eh? Talk about overkill! I have the HV767 in my truggy and even that on 2S has torque and speed to spare. I have been really impressed by that servo.
I had it left over from my Super crawler, from before I switched too 7980s, but yeah definitely overkill I dislike RX packs so probably a CC bec pro so I can run it on 12v. Otherwise I've got a few spare standard CC becs I can set to 9v for the time being.