I'll get some better photos soon of how it looks finished. Those hoses were just sitting there and have been moved to where the tank is now. Managed to swap out the headlights for LEDs but haven't tried them yet.
Changed out the diff oil too - but it didn't look or smell too bad, I think someone had replaced it not too long ago.
For those who are curious, yes you can fit a 4" pipe even without squashing, but we're talking only millimetres to spare.
Ohh... so what you really want to know is how does it go...
It doesn't seem much faster but I think it's not putting that much fuel in. The whistle is far louder and always present and overall I'm wrapped so far, especially for the cheap cost.
Time will tell how it goes. The exhaust needs to be finished off soon, its too short, too loud and vibrates occasionally with the heat shield under the floor.