This comes up from time to time one way or another. I have thought about just doing a drip test on the pump not caring where the marks are. Then look at the marks when you have established the drip cutoff. Crank should be about 24 degrees btdc and cam mark should be in the top quadrant. . If it turns up to be not the case slide the pump out carefully rotate the engine to the right marks and slide the pump in. Do another quick drip test to make sure all is well and off you go. The only other thing is the pump stiff enough to hold the last setting? Especially when removing and installing?
The chain sprocket or injector timing wheel is trapped in the block so should stay okay when rotating the engine with the pump off I think. Others should comment. As I never tried this. Yet if that timing wheel will stay in place it should work. Do this with the injectors or glow plugs out of course.
I know the other way just wondering if this is less complicated and easier to pull off? Do not take it to the bank unless a couple of other members think it has validity. It is more food for thought at this time than anything.