engine case bolts

[Meir]

hi guys.
about to start my clutch,IMSB,RMS...
in the Bentley book, it say to replace 4 bolts that connects the 2 parts of the engine case, when doing the RMS job.
this picture shows 3 of the 4 bolts mentioned in the Bentley book:



i guess its one of the "while you in there" type of thing.
however, i didn't see any reference to that on Wayne's article, or anywhere else for that matter.
is that necessary? or is it an overkill?

also what is the green stuff on the IMS cover stud?
thanks.
Meir.