Excellent post. Not i some vain attempt to draw attention to myself, but I shorten the stroke on my VG30 to 76mm with a custom crank and bored the cylinders out completely and put wet sleeves in. In the end costs were .... well..... lets just say I could have purchased a new car for less. I am still working with the engine as a lot of things happen when you do significant things like this. Just have a really thick cheque book.. Seriously if you want a bit more torque, just turbo upgrade.
Kirill hit the nail on the head A nice big thick wallet will make it work easy Your going to need: New engine and gearbox mounts Rewire the whole thing New driveshaft New exhaust manifolds And probably a whole lot of other stuff too.