Fitting an OEM hood will be a major pain in the ass and no-one in the UK that I know of has the level of skill as bodyshops in the US that can carry out this work.
Your best bet is to speak to organisations such as hyperturismo (www.hyperturismo.com) or CA Autmotive (www.ca-automotive.co.uk) and they will supply you with a custom made hood to fit your standard saloon hinges and fitment will be perfect. THey can also supply the hoods in carbon fibre.
Alternatively, if you DO know a place that can carry out some high-detail bodywork, get them to punch in a power-bulge in your existing hood
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