inlet manifolds

hi just wondering if some one can help me a bit as you all sound well clued up on things. if i had a b18c4 out of a 1997civic 5door VTi could i make a new manifold for it myself ? what is involved and are there things like chamber size that must be taken into account.Also is there a smaller one from another honda that would fit or an aftermarket.i ask this question as i want to put it into a 92 rover mini but as the inlet is so big it will not fit.
i know i could go for throttle bodies but that is very expensive.
thanks guys
jon

Ok, I don't have a B-series engine, but you should be able to take any intake manifold from any B series engine like a b16, another b18, etc...and it should fit on there.