Did you try the focus-assist from the Cine-cameras? I found to be insanely precise with the 85 f1.4 L.I tried my 50mm Macro and 100L with the camera briefly, snapping a hand held shot of a couple of flowers that have not yet been frozen this fall. It seemed to AF very well at relatively close distances. I also tried a 55mm Nikkor AI macro with adapter and focus peaking. That was no go, the focus peaking is just not precise enough, or I am moving slightly so I'll need a tripod to check that.
This is the 50mm f/2.5.