No that won't work Gareth. The P6 gears are too short to run inside an SD1 timing cover. If you want to run P6 oil pump gears, which are less efficient that the SD1 oil pump gears, you will need to remove the SD1 timing cover and fit an entire P6 timing cover with P6 oil pump gears. You can fit an uprated oil pump into a P6 timing cover which consist of taller oil pump gears, but you will need to install a spacer plate so the front cover can be fitted to the timing cover. If you do this, then the wobby drive is not fitted to the distributor.
If the distributor is causing problems, then best to replace it by itself.
Ron.