for the most basic stuff you can do yourself, even if you cant really wield a spanner its still quite easy and simple to understand.
1. flush radiator / replace coolant - google the rb25 manual, its free and download, tells you how to do all that
2. flush engine oil / replace oil filter + motul turbolite 10w-40 - turn into an asian with small hands cause you'll need them to get the oil filter, may aswell buy a relocation kit while your at it. Also put some proper oil in it Mobil 1 fully synthetic for instance.
3. injector flush - get some injector cleaner and run it through a tank
4. replace the clutch boot fork - ring nissan and quote this part number: 30542-69F00
5. clean aac valve (will do this myself) - swoit buy some gasket silicone (its made my loctite i think and its blue) and i gather you found the tutorial
6. clean throttle body (will do this myself) - swoit buy some gasket silicone (its made my loctite i think and its blue)
7. Would it be good to replace trans / diff oils at the same time - yes may as well again use a nice oil Mobil 75-90 in fully synthetic (if you track car) or mineral if its just on the street.
8. As for turbo lines, get a can of degreaser, spray the area, take it for a reasonable drive and inspect. All nissan motors seem to think oil is evil.
hope all goes well, otherwise hitup dan as the above members have mentioned.