Ok, I'll go into a little more detail on the stab:

As I said earlier, mount the wing.

Now put the stab in place - measure both sides to make sure it is centered, and measure from wingtip to stab tip on both sides to be sure the stab is not cocked in the "Yaw" axis. (Note: if you don't have a long enough ruler to reach this, you can make due with a scrap stick. Even gluing a few scraps together will work, but DON'T use a piece of string. String can stretch and give you an inaccurate reading)

With the stab aligned, "Eyeball" from the back to make sure it is aligned horizontally with the wing. If not, sand the stab saddle and repeat the previous 3 measurements.

Once it all lines up, put it in place with 30-minute epoxy (You'll need the working time)

Repeat the 3 alignments steps again. (I never said this was going to be quick) You can use small slivers of scrap balsa to shim the stab horizontally if need be.

Once it is aligned to your satisfaction, you can do one of two things. Either walk away slowly and re-check it ever few minutes to be sure gravity didn't make anything settle, OR add a drop or two of Medium CA in certain areas and accelerate them to hold the stab in place. THEN walk away slowly and re-check every few minutes.

Don't just think that once it is aligned it will stay there! Keep checking for about 20 - 30 minutes until the epoxy has started to set.

I do not recommend using pins!! The force of pushing a pin through the wood is more than enough to knock things out of alignment.

After a while, the epoxy will be set enough that you can leave the room to have dinner, beat your wife, watch TV, or whatever else you had planned, but don't touch the plane for at least an hour or two so the epoxy really has a chance to set.