Oil - drive shaft seals

Fishing around under the van doing the reverse light switch, I noticed that there is a slight oil leak on each of the driveshaft seals where they enter the gearbox. This needs attention. I was planning on replacing the gearbox oil, so will now do it all at the same time. I am tempted to drop the gearbox out completely so that I can have good access on the bench, but am not sure if I am feeling brave enough yet.

For now though it is the annual time of crossing fingers hard - the van's MOT has expired, so I need to get it tested ASAP..