After haveing completed the installation of the dual Hard Drive, I have to say that routing the SATA cable was the most difficult part of the whole procedure. The SATA cable is quite short, there is little space in the cable slot, which makes the power cable already there to leave its position. The Airport Cable is always in the way. Finally, I had to cut a piece in the cutaway in the plastic frame near the optical drive, just below the GPU heat sink, so that the SATA Cable fits. Perhaps a slightly longer cable would be more helpful.
In the kit i ordered, there was a SATA Cable with an angulated and an straight end. I would suggest to insert the angulated end in the board connector
Actually, if you have gone that far, there are only approx. 2 cables left on the other side of the board (As I recall the power connector and some data cable), so that if you want to access the CPU, it is then a small step removing the whole board.
In my case, all the cable connectors were oriented having the golden contacts, as seen from the wide side of the connectors, oriented facing away from the board
The display is quite heavy, an is fitted with a tight tolerance. I found it very difficult and dangerous, lifting it with any tool in one corner while the iMac was lying down. Instead, after removing the T10 screws, it was quite easy pulling the display out of the iMac with my fingers on both sides, while the iMac was in the upright position. By doing that, you can easily hold the display with one hand and reach for the connecting cables with the other