Hi Max and congratulations on your new Revolution!
I don't have the Sidekick, but have an opinion or two anyway.
When the AI gets a decent breeze, there can be a bit of extra spray in your face from the amas and front crossbar. The extra weight forward also keeps the bow down so it ends up driving through the chop and small swells. This also contributes to the wetness. Of course, the Adventure hull is a bit wetter than the Revo anyway. For these reasons, I think the aft location will be a drier choice for you.
Additionally, the Revo deck plan leaves you virtually no place to mount the Sidekick forward anyway. You can't have it where the drive mounts; you can't put it on the front hatch, and further forward than that, would be impossible to reach for adjustment, and will probably interfere with your steering stability, etc. etc. Forward mounting might be a more viable option on some of the other boats possibly (tandems or Outback for example).
Mounting it behind you will keep you drier, it will be easier to reach for adjustment and stowing underway and is where the flat mounting surfaces are. All you have to worry about is interference with your paddling stroke and possible conflict with any other gadgets you may want to mount in the cargo area!
It's nice that it has the flexibility to mount where it can best suit your needs. Hopefully, it won't be too much of a compromise with other space requirements. It seems to be very popular so, once you decide exactly where to place it, no doubt you'll really enjoy it!