Right, some answers to questions. The Mounting holes were drilled to 6.2mm to suit the counterbore tool and the 6mm SHCS are under 6mm when measured. Also the tee nuts can slide slightly in their slots so I am confident in being able to get the chuck concentric with the table. If that is not enough movement, I will increase the mount holes to 1/4″ and turn the heads of the SHCS down by 0.010″ diameter. There is not very much room for drilling the table top for direct mounting of the four jaw, but I will look into the possibility, and will remove the top for close inspection. The 6″ Soba RT that I also have has four slots and tee nuts and SCHS for direct mounting of the 6″ lightweight Toolmex four jaw independent. I did drill and tap three 8mm holes in the top to hold a front mount Pratt Burnerd 5″ three jaw scroll chuck. Not without a hitch, though. One of the first three holes I made ran into a drilling for lubrication in the top and all three were plugged and the alternative set were successfully produced. The chuck has sufficient movement before the screws are tightened to allow an MT2 test bar in the centre to hold the chuck jaws central within 0.001″ tir which is good enough for most jobs. The Soba 6″ has adjustment for backlash, but I haven’t looked hard for that on the 100mm one yet. The adjusting screws may be hidden under the paint. I am not sure what the central hole size is yet, it seems to be tapered, but is probably straight, about 20mm and a custom alignment bar could be made easily.