Mancini XHD springs :(

I had the same issues with MP SS springs (Two RH sides).

I need to get them De-arched, as that will help the wheel-centering issue, but my wheels are NOT centered evenly front-to-back, from side to side on the car.

How can you blindly shim the front hangar without an alignment? Wouldn't you risk pushing the rear out of allignment? I've seen plenty of old cars that dog-track.