France is easy, even with de Gaulle around - pre-empt the GPRF with the original plan to include France into AMGOT's jurisdiction, although in that case France would be in a similar situation as Austria. It would sound weird, but it would at least allow for people to directly confront the Vichy legacy head on, as an actual French state for a period rather than an illegitimate one. And then, have it grow from there.
As for the UK, though, the problem with it is that it was so bankrupt it couldn't even afford to pay for becoming more "Gaullist". It could try, including trying to bring the Dominions on board with it - and yet Canada would be among the first to be very wary of what's going on, given its close links with the US and its own domestic issues (not to mention going against Ottawa's policy at the time). Ultimately, this would mean the UK would be in an uncomfortable position in the long-term, with internal divisions coming more to the forefront than they otherwise would be (and not just in Northern Ireland).