Really easy. Buy new seal from Renault. Approx. £12. Jack up and make safe with axle stand. Remove OS wheel. remove 34 mmDS nut. Loosen and remove 24mm nuts from strut to hub assembly. Remove top 24mm bolt to allow hub to swivel. Remove both 10mm bolts holding mid shaft bearing locking plate. chap out drive shaft from hub and guide past brake caliper. Carefully slide driveshaft clear. Leaver ot old seal. Replace with new one.
Refit in reverse order and tighten to spec.
Check gear oil by removing plastic thumb plug on end of box and fill till overflow.
Well done, job done.
John S
December 2007