I don't know of any bolt on packages for the TDI. I suspect that you have already seen these pages and they are the ones causing your head to explode.
For power options/levels, what is needed to get there, I refer to.
I also look here for power options and parts, although finding power options, what is needed, on his site is a little more work.
This is the site I use to buy most of my parts. I use IDParts because they have great service, I know the guy, he is local, he has a good idea on what works with TDI's, and what doesn't. With a bit of searching, you can do better on pricing though.
Can you be more specific on power levels you are looking for? Since you have a 99.5, you have a better clutch and if you stay at reasonable power levels you won't need to change it. The clutch on the later models is only good for 200ft-lbs, I think yours is good for between 225-250ft-lbs.