Follow this instruction if your USDM STI TMIC came with a y-pipe.
You will notice that Y-pipe to turbo hose is about 1" short!
Order 2" 90 degrees ID hose here for $38 shipped. You will have to cut about 1 cm to create a perfect fit.
Brackets will not align with the intercooler on passenger's side. It is perfectly normal for USDM TMIC to not correctly align with brackets. Why? because throttle body hose is about 0.5inch short.
Intercooler to TB hose is about 67mm ID (too short @ 2" in length). You can order a 2.75" ID turbo hose (3" in length) from here if you decide to correctly mount both brackets. http://www.stylinmotors.com/turbohose.html
WRX splitter and seal won't align correctly!
order air splitter and seal kit from rally spec
RST-9085kit Air Splitter & Seal Kit MY02-03 $84