Hi all, I'm having problems with the O/S driveshaft seal on my '93 R5 1.4 Campus - oil leaks from the seal where the driveshaft goes into the gearbox, I have fitted a new genuine oil seal but it still leaks, there's an o-ring which I'm not sure about, does it just slide on over the splines before the driveshaft's fitted or is it meant to tuck inside the oil seal? The Haynes diagram isn't clear and it isn't mentioned in the text