Originally Posted by
BCRider
This suggests to me that the rear caliper is now cocked at an angle to the seat stays. The tube nut would act like a bushing on the front side of the hole but not at the back. So the caliper will assume an angle closer to vertical instead of mounting parallel to the seat stays. This angle is likely what is allowing the caliper to reach down a little more and work for you.
You could get a different fork or you could get some longer reach side pull dual pivot Tektro calipers. If you want to run with fenders the longer reach option would be the best.
No, that's not the case. The caliper is parallel to the seat stays and seams perfectly aligned with the brake surface of the rim. There is no issue with the rear brake. I don't intend to use fenders and am leaning to a different fork although fixing this problem is making a shambles of my budget. Oh well.