If the parts are opposite of each other just put a diverter on the spru picker that sends two part one direction the other two the opposite. Build a separator under the molding area that send two of the parts to a different location.
Its a simple and cheap solution.
Family molds #*^&$%*%&~!
Well, as for the surface runner molds that you look at in the future, use a Melt Flipper. This will solve the problems of balancing a poorly laid out surface runner molds. Never try to gauge primary to secondary runner and increase or decrease diameters to accomodate a filling imbalance.
The...
Look at the X melt system developed by Engel. It will give you the abitly to fill this part so extreamley fast that the cavity pressure gained during a normal injection filling process will not come into effect.
It works very well for thin walled parts.
