Hi. I have an F550 which was built for me by the supplier. I have bought an H3-3D gimbal and want to replace the H3-2D on board. I have bought a FlatTop adaptor http://www.helipal.com/product_info.php?currency=GBP&products_id=11650 but could really do with some step by step advice. I'm a complete novice solderer but am keen to learn and have never taken the top plate off before so I'm a tad nervous. Where are those YouTube videos when you need them? Hope someone can help.