A lead assembly comprises an outer body tubing, first and second conductors, and first and second tubing insert members. The outer body tubing comprises at least two longitudinal outer body tubing portions, each such portion comprising a through-hole and each portion comprising a keyed surface having a predetermined shape. Each of the tubing insert members receives a conductor and comprises a surface that substantially matches the predetermined shape of the keyed surface. When both of the conductors are inserted into corresponding longitudinal through-holes such that each of said first and second surfaces of the first and second hollow body members is substantially aligned with the keyed surface of a corresponding outer body tubing portion, electrodes formed on ends of the first and second conductors are encouraged to be substantially co-linear.