There is a description on how to use the kit in the Factory Service Manual CD set. (Merced*s Sourc* has copycatted part of the kit; they might have instructions at their site.)

The Wire and Pin vice are indeed used on Mercedes to clean #14 and #15 in the picture of the Injector Below.

Some of the other stuff is various sized scrapers to scrape the Seat in the Nozzle.
I have not used the Bosch Kit before but Stanadyne had a kit (around 1973) for their Pencile type Injectors that had similar scrapers.
What I/we found out where I worked was that the scraper saved very few Injectors. And, for use was not worth the labor.

The reason the scraper did not work better is that the Pintel hammers the seating area in the nozzle and itself; bits of Carbon get beat into the metal and the high pressure of the Fuel erodes the surface of the seat.

The damage to the seat cannot be scraped out.

In order to use the Pin Vice and Wire effectively the Wire must be smaller than the hole (the manual tells you what size to use).
Not in the manual. Where I used to work we would grind a Hypodermic type point on the Wire and carefully drill into the Carbon Plugged tips. A flat ended wire is not very effective.
This might not happen to a Mercedes Injector Nozzle as the holes are big in it but on the Direct Injection Nozzles when the were picked out with a Wire sometimes the Wire would break off and also sometimes that wire was not coming out either.

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel