Sure. Plug one servo into AUX 3 and the other into elev. On the 8103, first deactivate Aux 3 from the lever. Do that by going to a P-Mix and mixing AUX 3 to AUX 3. Set the mix value to -100% in each direction.

Now go into a second P-Mix. Choose one that includes trim (makes the slave channel move with the master trim lever). I dont remember which ones those are on the 8103, but its in the manual.
In that P-Mix, set elev to Master and AUX 3 to slave. Set the mix values tso the total travel of the slave elevator is the same as the master elevator. Thats it.