I have started my control surfaces bodywork, On the control surfaces, 
do you build up their level with the surface leading it, or to the 
level where it meets/pivots.

For instance, I am starting on the Horizontal Stabilizers and 
Elevators. Where the Elevator, meets the Horizontal Stabilizer and 
pivots into Horizontal Stabilizer; Should they be the same level. 
Meaning building up the Elevator with Micro, or should the Elevator 
be at the level that they meet... About 3/16" lower.

On one hand it seams aerodynamically the build up and leveling will 
not create as much air flow disturbance, but at the same time adding 
all that Micro would be extra weight?

Kevin,

 

Any time the airflow sees a step down there is turbulence, loss of attachment, an increase in drag and, perhaps, some loss of control surface authority.  In the small operating range about cruise speed, the control surface should be at least at the same level as the attached flying surface or even a bit larger as the air can follow a minor curved elevation (no pun here) in the surface over which it is flowing.

 

Too bad that fast build parts sometimes don't meet one's requirements.