I guess if your tie rod has "shortened" due to bending, it would skew the center of wherever you measure from, and make it seem like the WB is off but it is not. You are right in putting a new tie rod on, adjusting it so that the hub or wheel is parallel to the other side and both are perpendicular to cross member centerline and then measure WB again. Remember, if you are using a regular tape measure with two people, the tape must be held to exact centers. A tape measure is not a good method. You have four places to be off with holding a tape by hand. Only 1/8 off, 4 places, to get a 1/2 inch difference... and slack in tape two times. I hope you devise a fool proof method of measuring before making any further adjustments. WB measuring example using a straightedge: use an aluminum extension ladder section and mark it. This rigid, straight, non-sagging ladder piece can be set up by yourself. Even a 2x6 may work. Try taking off all wheels so you can "kiss up" to the hub centers for accurate measure with the straightedge.
