Hi Krisso, firstly good luck with your build. Done right it will be more powerful than a TT with BPU and for less money! The kick from a single on boost should put a big smile on your face even at 6psi. Me and a friend dit the NA-T conversion on my supra jus over 2years ago now and i've never looked back. My build achieved 374BHP and 404NM torque on the Dyno. There af few pic's of intercooler piping and my spec here:- http://www.mkivsupra.net/vbb/vbpicgallery.php?do=view&g=3373
I took the oil feed to the turbo from the oil filter housing as there are two blanked off fittings there, i got the braided oil feed made up by a local hydraulic specialist. I can't remember off the top of my head which one is the feed tho, maybe someone on here could tell you.
For the oil return i simply used the TT return flange bolted to the sump and blocked on side off as only running a single turbo. I did remove the sump to do this. We managed to undo the engine mount bolts and drop the PAS rack down, then hoist the engine up a few inches to gain access.
Good luck, let me know if you need any more info.