Aside from the headset install and fork cutting, the rest of the job could be done with a well-equipped multitool. My only comments are as follows:

1. Be careful replacing the Grip shifters with Rapidfires and changing derailleurs. You need to be sure that the Rapdifires are compatible with the road derailleurs as the pull is different than with the MTB derailleurs you currently have. There are Rapidfire's that will work with road derailleurs but most won't.

2. I personally would not bother with the drivetrain change, aside from swapping out the Grip shifters (personal preference). Assuming you have a 48 big ring on your crank, going to a 52 on the road crankset won't net you much more top end speed. Also, if your new cassette only has a 12 top cog like most road cassettes do and if your old cassette had an 11 like most MTB cassettes do, you will actually be losing top end speed. Unless the weight difference means a lot to you, I'd stick with what you've got.

3. You'll probably not even notice the suspension seatpost is gone. Swapping out the suspension fork will make a huge difference in road feel though.

4. Those Ergon grips are fantastic. You'll love them.