Thanks to the stickies, I know how to get to my CYMA M14 gearbox. I'm going to open up the gearbox, do some DIY mods, and hopefully everything will turn out fine. I've opened a v2 gearbox before, but that's it. Basically, I want to stabilize my barrel, correct AOE, regrease and reshim, tape my cylinder, and floss my hop up. Here are some questions/verifications: 1. Is floss noticeably more effective than tape for the hop up? 2. To shim, I need to make as little side-to-side wobble as possible without misaligning the gears, correct? 3. I grease gear teeth and the side of the piston, right? Anything else? 4. Do I tape under or over the O-ring? 5. Can I use any spongy material for padding the piston (to help correct AOE)? Thanks in advance.