When you get to the trim servo part, I have some suggestions. They apply to the -7, but I am not sure if they are applicable to the -9.
A) Wait until you have the trim tab mounted and the position of the trim tab horn is known before mounting the servo brackets to the cover. In addition, don't blindy follow the instructions (dimensions) on the plans for mounting the z-brackets to the cover. Instead, draw a line where Van's wants you to and then verify the alignment with the servo attached to the brackets before drilling any holes. I found, and I have seen several others, where the servo has been off to one side by as much as 1/8" when the dimensions given are followed without verification. Go
here and
here for pics and a better explanation.
B) In a similar area, don't dimple the aft holes for the trim motor z-brackets and cover. Use Oops rivets (NAS1097) instead. If you dimple the aft holes, the shop head of the rivet can prevent the motor from sitting flush against the z-brackets. It happened to me on the -7, and it may not be and issue on the -9, but I have seen (online) where it has happened to others. You can always make a shim or use washers, but if you use Oops rivets, you don't have to. Pic
here.
Good luck!