P38A Camshaft positioning tools

Hello all, Can any one inform me of the importance of the Camshaft holding tool (LRT 12 112) or if there is another way around it when you remove the camshaft sprocket.

What type of head is fitted to the bolt securing the camshaft sprocket.

(about to remove the head on my 2.5 deisel) just want to make shure I have everthing covered before I start.

Regards Dutch RR

Holding the camshaft is v.important, as is locking the fuel pump and crankshaft. If all these are not lined up with mucho acuracy when re-assembling, she aint going to work no more. You only have to be a fraction of a degree out to seriously affect the running.