Replacing a starter- how difficult?

[0396]

First, I apologize if this has been discussed before.
My 2004 S4 exhibits what I consider a failing starter.

When I turn to key to start it, it simply drags as if it was under stress. I think is due to the actual starter and or the solenoid slowly engaging.

Either way, since I already have a new spare I bought off this forum, think its time.

So my two questions:
Is my analysis correct?
Also can I replaced it at home and how difficult is it?

Thanks for your assistance

[tmorgan4]

http://sandbox.enjoybeing.net/diy/S4/starter/

[0396]

Tmorgan,
A Big Thank You,
It's exactly what I needed.