By your original picture, it looks to me like if you ran on the front pulley on the Alt, your belt alignment might be a little better. Might be the angle of the picture though. Do you have room between the back of the Alt and the head to move that alt behind that top bracket and re-size the spacers to gain belt alignment?

I've also seen where if you can swap the 2 grove Alt pulley for a single grove alt pulley, the belts align pretty close on some applications.
Gene