Rebuilding a 1968 109 with a 2.25L petrol. Had the block redone, crank and pistons installed by the machine shop. Refitted the camshaft, set up the timing with little issue. Now installing the oil pump drive gear.

Just trying to put the oil pump drive gear back in and final lined up the master spline, when I try to line up the hole for the grub screw, I have to lift the whole body of the drive gear up about the length of the hole to get it lined up, which means the whole thing will be resting on the grub screw, is this correct?

I never took apart the oil pump drive gear assembly and I don't have any bits that appear to go under under the gear for it to rest on.

Many thanks for any thoughts and advice.