Nathan, I find it much easier to balance the wings alone, without the fuselage. Join the wings the usual way, mark the center point on the joiner and balance using a knife edge under the joiner. If a weight is required, then drill a hole thru the wing tip ply for a cylindrical weight. I only had to use a couple of 1/4 inch threaded studs about an inch long and used elmers glue to secure them. Then capped the hole in the ply with a 1/4 inch dowel and used a small covering patch. Most lateral imbalance comes from the wing, and I wouldnt be too concerned about any small offset due to the engine horizontal mounting. Then if the plane still dips to one side you probably need small adjustments elsewhere. [8D]