The older lower rack in the photo above is Wright rack, the upper is a off shore copy. One of the biggest complaint about the off shore racks is the lack of turning radius. This is caused by a shorter slide slot and the adjustable stops.

There are two thing you can do to increase the turning radius.
One is to remove the stop bolts which will allow a little more travel.
The second is to remove the stop assembly and cut the slot 5/8" longer on each end to match the Wright rack. This will allow a substantial amount more turning radius. The last photo shows a comparison of the original and the modified slot. The adjuster can be welded back on if desired.