Looking good. The bike was a good score.
You do need the mount, glad to see you went with Sick Bike Parts gear. From what I have seen, they are the best to deal with and can offer advice on the parts they sell you.
Have you got the clutch worked out?
You can attach the 'control box' with cable ties in place of bolts. I think your frame is too big for the bolts that come with the kit.
I also remember reading on this site about the tank spacers for bike with cables running down the top of the frame. You don't want a loose tank. If it can go wrong, it will. Try searching the fourm for this..
When I put my kit on, I was in a hurry to get it on the street and didn't put the tank on well (same reason as you, cables) well after it fell off, I had to find a new tank...
When you are ready to roll, it should be all fun!