I thought of the reverse scenario also being explored in this thread myself the other day; wondered if the ancestrally Democratic parts of the Upper South like Middle Tennessee might provide an equivalent to the holdout liberalism of the Celtic fringe.
Yes, those are areas which I always find difficult with exercises like these (same applies for rural Arkansas). Too rural to vote Labour, arguably too poor to vote Conservative. I think they'd be a good fit for Conservative now, but in Tony Blair's time? Much more ambiguous. Could really do anything and might come down to how Southern traditions would've blossomed in this hypothetical scenario.
Poor rural areas in the UK (excepting those with with an industrial presence) have tended to default to the Conservatives, albeit not always happily.
They're the sort of areas that have often flirted with the Liberals (much of the West Country, Herefordshire, etc.) but places without a Liberal presence generally defaulted to the Conservatives in a straight blue v red fight. It is notable, for instance, that the collapse of the Liberals in rural Lincolnshire did not lead to Labour winning any seats.
Thing is though, there aren't really poor rural areas in the UK in the same way as America. South Holland isn't Mole Valley but it's still far from anything in America.