What do I need to do injector change?

["Henry H Kim" <henryhkim@xxxxxxxx>]

I've got a hard starting problem on my '89 325iX plus a rough idle (not
fluctuating revs but just an odd, pulsating rumble).  My mechanic diagnosed
4 leaking injectors and having recently spent $1,700 with him, suggested I
swap them myself.

I'm planning on replacing all 6 injectors instead of 4.  I don't have my
Bentleys yet (on order) and I've never done any engine work before other
than tightening belts and replacing plugs.  So, I want to make sure I order
everything I need.

I'm ordering six new injectors and o-rings.  Since I have to remove the
intake manifold, is there a gasket that I need?

Also, forgive the seemingly obvious question but what is the role of the
cold start injector?  And where is it?

------------------------------