Injection pump timing- reassmbling the engine

[New2MB]

I have a situation which seems a bit unique, I am putting my 1987 300SDL back together after not touching it for over a year and a half.

I have the oil pan, timing cover, and head off so I plan on installing the head first, then the timing cover, then the oil pan.

Getting the valves timed seems easy enough but I'm a bit confused about the injection pump. Everything I have read so far assumes the injection pump is somewhat close to being timed. Mine is uninstalled and unmarked.

From my manual it seems that I am to turn the engine to 15 degrees ATDC on cylinder 1.

Next I use Serrated wrench special tool (damnit!) 601 589 00 08 00 to position the locking bolt and then tighten the union nut.

Then I install the injection pump, remove the locking bolt, and this should get me close enough to fine tune it once it is running.

Sound like I've got this correct?

Any way to avoid having to use the special tool?