AGSP scoring blade height problem

[RTK]

Hi everyone, I have an AGSP saw that I’ve just started re building the scoring blade set up on. The previous owner had given me the pulley tension bar without bearings and pulley, the scoring blade spindle was in place and working. So after some calls to Wadkins I got all the bits. It all went together perfectly but I can’t get the scoring blade to rise above the table, it sits about 10mm below when the main blade is 30mm up and pretty much flush when main blade is fully down. Is there something glaringly obvious I’m missing? Next step is to take it all apart but I thought I would seek opinions first. It has a 250mm main blade with the wadkins 105mm scoring blade. Also, does anyone know where the serial number is on these, I don’t know if it is actually an AGSP. Thanks in advance.