Replacement drawbar turned up yesterday with a FOC hardened washer to support the drawbar above the spindle. I believe the washer as supplied is not hardened. It is also 1.5mm thicker so pushes the splines on the end of the drawbar a little further into the drive nut (called a clutch by Gates).
Rather than turn the head 90 degrees to remove the drawbar found it was easier to just nod the front down by about 20 degrees and this gave enough clearance to remove and refit. Powered it all back up and pressed the button to pull a tool in, all okay. Pressed button to release and all back to normal.
At least the drawbar was the cheaper of the possible options.
Jut have to tram head up now.
Colin