Finally got back to this. After some thought I found a way to print in one piece without supports for the clamping block. With an angle of 60 degrees and adjustment in the slicer the block will print without support. That left the holes, I got around that by covering them up with a 0.2mm layer that can be knocked or reamed out on completion. This with removal of some of the meat on the block reduces the print time by half to 18 hours at a speed of 40 mm/s and more at higher speeds. With the block angled the clearance from the router is reduced by 5 mm. I don’t think this is critical but if so the plate could be lengthened. As I said earlier I haven’t got a router to test all this but if anyone wants the .stl or the Fusion .f3d files to print or improve, PM me and will I send them.