Hey everyone. I've had a broken Galaxy MP5 for a while, with the gearbox apart. I took the gearbox apart knowing what i was doing, but there are no good sites on the internet on how to put the gearbox back together, because of the weird shape. The only trouble was the piston was crap, so i want to get a better one, but i cannot because i still can't put it together again. Which is the best airsoft site i can trust that will replace my piston and put my gun back together in one piece? thanks.