Thanks everybody for your valuable suggestions.

I am still awaiting for parts (EGR valve Gasket, EGR pipe gasket, PCV valve, Breather hose, PCV hose, Engine Air Filter & Throttle Body Gasket) from the parts dealer.

I have never a serviced a car before, so i am still going through the Service bulletins to make proper repair plan. This weekend, I plan to buy a Torque Wrench, can somebody advise on type (Ratcheting, click type, Snap on,etc, toqrue range, manual/ digital)? i m a newbie..

Do i need to take off the intake manifold for cleaning? as i see deposits of oil inside the upper part of intake manifold.
Reading from the Service bulletin, I need to get rid of Fuel system pressure first to be able remove fuel rail first. This will help to get better access to intake manifold bolts.

i am not yet clear whether I need to drain the engine coolant before removing intake manifold. Surprising, there are no instructions in service bulletin related to this. I just dont want to get into any trouble ahead...

There is an adaptor to which the EGR valve is bolted, it has heavy carbon deposits inside the ports for EGR valve & EGR pipe. I need to to remove this adaptor as well. Its not clear to me, if coolant will bleed after removing this adaptor.

Advise on all these points will be of great help to me.. I am eager to receive your responses. thanks..