Running through my method for setting up steering.

First thing to do is make sure the tie-rods are the same length. You should never run unequal length links (unless you have an old xray with an off centre mounted steering system), as this will mean you don't get equal steering side to side.

Then I'll make sure that the tie rod to the steering systems is at a perpendicular (90°) angle to the servo horn. This is allow the steering to have equal steering throw side to side. On my 416 (and 415 previous to that), that means that when the steering is centred, the top of the horn is pointing in towards the centre line of the car. Adjust the position of the horn by firstly zeroing the servo then lining the horn up on the spline closest, then adjust your sub trim till at the right angle.

Then attach it all up and place on the gauges (making sure to push the wheels back). First job is to get the steering straight. Adjust the servo horn tierod until there is equal toe both sides. When thats achieved, you should then be able to adjust the L/R steering tie-rods equal amounts to obtain your required level of toe. I also check the steering throw levels on the gauges, which I can then fine tune using EPA adjust on the tranny (although if everything else is right, it shouldn't need much, if any tuning).

Now the steering should be dead straight, with equal side to side throw, and the required level of toe.

Sounds like a lot to start with, but once you've worked through it a couple of times, it becomes pretty easy to figure out.