I would take the whole thing, transformer and board, out and place it on your workbench, lots easier to work on it that way. If you are more comfortable leaving everything in the game do whatever makes you more comfortable. As far as E7--GI buss and E8--ground go, they are redundant points so don't worry about which hole, left right, up down, as they both end up in the same place. Just take your time and don't forget that new female connectors are part of the same job, too. Don't be afraid to use a lot of heat in the soldering process. I believe at last count I have installed well over 25 of these rectifier boards and the first one was the hardest. Good luck!