If i extended it at an angle steering would also become a problem it would only turn so far.
If you extend it straight out you lose nothing.
By extending the steering arms straight out, You Will lose something, that would be the Turning radius, witch isnt so great to start with on a rack swap.
That happend to be one of my first fixs after my first install. "Move the rack back"
But if you are going to mount the rack where it is. I'll give you your Tie breaker. Extend the arm forward so as not mess with the overall tierod length.
I wouldnt Weld it first either. I would Bolt in a test extension so that you would have another Adjustment point, in/out on your steering arm when plotting your Bump steer and Ackerman like Raff suggested you Do!
Then when you get those adjustments as good as they are going to get. Then you can weld your extensions on solid.
Another tip is to get your Caster dialed in first. As caster adjustments will move the outer tierod connection point at the steering arm up and down a significant amount. If your steering arm is extended by 2",s its extended movement is even worse.
This effects the parallel relationship between the tierod and the lower control arm mike
mike