Got home via RAC :(
After a massssive full bore take of at some lights, I learn the limits of Clio hardware:
CLANG!!! OH FFFFFUUUKKKK!!!! WTTTFFFFFXX?? CAMBELT? GEARBOX???? LSD????? WTFFFXXX NO DRIVE!!!?????
'HAI! IS THAT RAC???'
'Yes Hello, is that Mr Mumford with the Clio?'
'YE!'
'A recovery van is on its way sir.'
So, I stripped the inner nearside driveshaft tripod joint clean off we think...luckily, only 10 mins from home and the RAC guy happened to know someone else local with a Williams Clio...