When using tape to seal the control surface gap, I pop the clevis loose. Then deflect the surface all the way up and put tape across the bottom of the surfaces. This guarantees for me that the gap is sealed and the control surface will still move freely.

Plus, since it is on the bottom, it isn't so obvious.

When using hinges of the type you used, I normally make a small V notch on both control surfaces. This lets the hinge pin portion to fit into this. Also, I dab a tiny bit of Vaseline along both sides of the barrel on the hinge that the hinge pin goes through. This keeps it epoxy free.

You also might want to consider the "CA" hinges that look like flat, slightly fuzzy plates. You make slits on both control surfaces, slide these in and put a couple of drops of thin CA on both sides in both surfaces. These work really nicely, can give you a real small gap and are really strong - I have used them in planes up to .90 sized.

Finally, there are iron on hinges. These run the entire length of the control surface hinge line. You iron them on to both sides of both control surfaces. Never had a failure with one of these in planes up to 50 cc gas engine types.

Hope that this helps out.