Great thread. The ute looks awesome, I cant wait to see it in person some day. Regarding the 5 gas test I'm not sure I would be scared of it. I have had to do the test with two different cars for engineering and if I can pass it you can too. The first car was a 2003 Hilux 3.4L v6 using a TRD supercharger and full long tubes and exhaust system. We had no control over the engine management. Zero. The car was running a total factory ecu and tune with normal 98 fuel. I tried the test the first time and failed miserably. I replaced the 02 sensor with a new one and bought a euro 4 compliant cat convertor, my engineer advised me to do this. On the next try we got the engine (Mostly the exhaust system) stinking hot, for example it was sitting there for a good 4 or 5 minutes running at about 2-3000 rpm and it passed this time. So supercharged, custom exhaust, no custom tuning - pass. A good cat converter is essential here. The requirements for a pass change as the cars get newer, one benchmark is 2003 so I had to meet that one. I think the next is 2007 and the last one was 2010 (Might have changed its been a while since I was there). The tests were conducted at Roadbend Jaguar in Welshpool. Cost is Under $200 per test. This test isn't the IM240 that was getting spoken about at one stage, that is a totally different kettle of fish. This test is conducted at idle and at 3000rpm no load so most likely no boost in your car. My current "Fun" car is a 1995 200sx fitted with an 5.7L and 6 speed from a vx. This car has also passed the 5 gas test obviously engine swap etc etc needed engineering. It was fitted with long tube headers, custom intake and 2 cats from a vz ss. This car passed the requirements for a vehicle that was built in 2010! It only had to pass for a vehicle build in 2000 (Year of the engine). Running normal 98 fuel and with god knows how many km's on that motor. Custom tuning, this helps a lot if the person doing it knows what they need to do. Cats need to get hot. Really hot. On the 200sx we had the headers glowing. I presume the tuner manipulates the tune to increase the exhaust temperature at idle and at the 3000rpm point this heats up the cats and the hotter the better. This is why modern cars have cats as close to the engine as possible. My friend also passed a similar vehicle with a cam running a 228/232 - 113 LSA (lots of overlap means its emissions unfriendly) by mixing in a bit of e85. Which brings me to my next point. If you put that ute on e85 tune it up and there is a cat in there at all it should pass the 5 gas test. I'm not sure if any of the ford tuning guys in WA have had to deal with the 5 gas tests and stuff but turbo engines with stock cams should be a cake walk. Especially on e85. I also have a feeling that to get your car compliant using an aftermarket intake they are going to ask for the 5 gas anyway even if the exhaust is standard. So its either change intake and exhaust to standard or pass the test. . Having said all that ( Or written in this case). If you change the intake manifold and exhaust back to stock I don't see why you would need an engineer at all. Its just extra work and you can clearly handle that.