Ok, As I told you, I builded some SE but all kit version. Because I already made other ARF from SIG, I am sure that the procedure to install the wire is in the instruction booklet.
I am sure that a a friend on the forum who have a SE ARF booklet, will post a message or better a scan of the book with the procedure explained in a english better than mine.

I agree that your hinges gap are too big, and I hope your ailerons aren't like that. If they are, install a sealing tape or better, a strip of clear oracover.
If your rudder is already hinged also, be prepare to cut the hinges
because you won't be able to install the joined elevators with a hinged rudder (it's the case in the kit version, i am not sure for the ARF).

I think that a SE is a expensive stuff and that we must help you to corect your mistake, but you need to have a positive look on the wonderfull book you received with the plane.
You made a mistake, we can easily help you to correct it because it's not a dramatic one.
Before begining to work on a plane I always read the entire booklet and I don't begin to glue before I understand all the pictures and the entire assembly sequence.

Go backward, read completly the book, check all your previous work


this is my humble $ 0.00025 tip