Update:
My (severely) cut down stock intake manifold is here at work with me about to get milled flat, i decided against making a new intake flange this time as the stock cut down manifold will work fine with little comprimise.
Once it's milled flat the ports will be thoroughly re-shaped to get flow as straight as possible into the head, then my hand-formed tapered round-oval adaptors will be welded on, along with the first set of flanges.
Everything will then be ported and cleaned up again.
One other little design change i am making will be replacing the coolant return pipes with AN fittings to allow FAR easier coolant line hook up / removal for anytime i may need to remove / install the manifold again.
The single hardest job with removing / installing the intake manifold is those lines, getting the hoses on so they don't leak is the world's biggest PITA.
This new intake manifold is one of the major items that has to go in before i can even think about bolting up a turbo, my 1000cc/min injectors need larger bosses than the stock injectors to allow them to fit. (they are the 14mm double o-ringed type)
I decided this ITB setup is going to be the trial setup, depending on how this manifold performs will determine how much time and effort i will put in down the track on a complete one-off custom ITB manifold.