I'm in the process of changing my car to run fuel injection, so I've been asking the same questions...
Further to what Dave has already said, most injection pumps are gravity fed so if you only use one pump fed directly from the tank (as opposed to an external swirl pot), then the pump needs to be as close to level with the tank outlet as you can reasonably get it.
Also just to clarify on one point - by 'braided hose' I think Dave means stainless steel braid, as opposed to cotton braid which is only suitable for low pressure (carb) applications. I'm not sure how the law stands for IVA these days regarding stainless braided fuel hose, but you may find it needs to be correctly marked as 'fuel hose', in which case you'll need high pressure rubber hose. Don't quote me on that though - stainless hose might be fine.
Finally don't forget a filter. I'm fitting a small pre-pump filter to protect the pump from any crud in the tank, but may also fit a larger filter in the engine bay.
HTH