Ok, it's done! What a day, had a couple of things I didn't anticipate.
1. Two studs on turbo are about 60mm long to suit the standard dump pipe, this meant that to get the dump pipe off the turbo, it required the turbo to come out altogether, in the pic you will see the bit of tube I used on the long stud, also I had to remove 2 of the studs and swap them round to get the dump pipe on. One good point about this was I now know my turbo is in good nick, no slop in the bearings and it spins freely.
2. Holes on the turbo side flange didn't quite line up with the studs on the turbo, this required the holes in the dump pipe to be enlarged, had to go up about 1mm in diameter to get the studs through cleanly.
3. The brackets that hold the muffler up were about 2 inches long, which meant I had to cut them and weld back together to get the correct length.
4. The last stage of the pipe was longer than the original to the point that the pipe poked out under the rear bumper, while it looked good from the rear it was going to be a disaster off road. I've dropped the rear bumper on enough things to know that the next time I went out wheeling the pipe would have been crushed completely, the fix was to just cut the pipe back to the original length back next to the spare wheel.
5. One on going problem to still sort, the bugger is bashing on the cross member at the rear of the transfer case under medium to hard accelleration in 1st and 2nd gear, not sure if this is a problem with the pipe, or my engine and gearbox mounts are on their way out because when you load up the engine with the bonnet open you can see the rocker cover lean over a good 20mm, probably equals 4-5 degrees of twist.
Also I found if I swing on the tail shafts out of the transfer case I can move the transfer case up and down a good 20mm just with my own body weight.
Now the bad is out of the way, on with the good. The engine is a lot more responsive, boost is on a little earlier, where before it would only do 9-10 psi at 2000 rpm, it now does 12 psi, and by 2500 rpm it's up to 15 psi, it didn't use to get to 15 psi until about 3000 rpm.
Cruising on 100ks boost is sitting on about 10 psi, was 6-8 at this speed, exhaust temps are much improved, at 100 it was sitting on about 320 degrees C, on the old system it would site around 370-380 degrees.
Noise levels aren't too bad, got a deep burble to it at idle outside the vehicle, can't hear anything different inside with the windows up, and it's got a nice turbo whistle to go with it which sounds pretty horn.
New dump pipe versus old
Pissy Nissan bend versus mandrel bend goodness.
Would I do the install myself again? Hell No, I'd pay someone else to do it.
Do I think getting the exhaust done on a D22 Navara is worth it? Hell yes, the motor is just so much more snappy, boost is on sooner, and exhaust temps are lower.
Ok, I need a beer and a lie down, my back is killing me.