I am not sure wich vehicle you are working on. However, on my 1984 300D if I rotated the Engine in the direction of normal rotation to top dead center and coninued to rotate the Engine to 15 Degrees after top dead Center. Lined up there I could pull the Fuel Injection Pump out.
(At that point if you remove Plug where the Locking Tool is supposed to go you should be able to see the raised part that fits into the locking tools slot; or at least that is what other members have said.)

While the Pump is off of the Engine I would be able to see which Drill fit into the hole and would be able to make the Tool.

When I am read to install the Fuel Injection Pump I would look down the hole where the timing pin goes and rotate the IP until I could see the raised part that is supposed to fit into the slot. I would stick my homemade pin in and I would try to rotat the IP both directions to make sure it was locked and could not rotate.

The original tool is spring loaded so ounce installed you leave it alone till you remove it; the trickie part is that you are going to have to hold on to the homemade locking pin or find a way to keep it from sliding out while you insert the Fuel Injection Pump back into the Engine.

The slot on the original locking tool is not very deep. I had 2 of them and sold both not realizing that they would fit my Fuel Injection Pump.

However, I do not know if using the Locking Pin means that you do not have to in my case Drip Time; it just gets you in the Ball Park (due to Timing Chain/Gear wear).

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84 300D, 82 Volvo 244Gl Diesel