I got around doing it now. Taking the box apart was actually very easy with a good set of standard tools. Taking out the gearbox was however a bi...ch. My dads lift couldn't cope with the weight of my (fully laden) car so had to do it the bush way, that is, roll up the front of the car on a set of spare wheels and crawl around as a greasemonkey.
Now to the conclusion this far.
As suspected, the rear roller bearing on the layshaft is busted. Looks as the damage was caused by debris from the two teeths missing on the fifth laygear . The other bearings appear to be in a fairly good stand and so do all the other components. Eg. Mainshaft splines are as new, syncros look as new and so on. Weird, I have covered more than 200 000 km with the vehicle. Anyway I will get the maste rebuild kit from Ashcroft as the bits are apart.
The bad thing is as follows. When I took the oil pump to out I discovered that the hosing is pretty worned out, in particular where the impeller tap/shat is supported and also the surface at wich the pump ring rotates against. I'm not quite sure how critical this is in a gearbox, in a engine it would be consideed scrap. This means that either I have to do a lot of machining and insert at bush both at the tap and the outer surface or buy a "new" housing. Although I find it od that there isn't any wear in any components so there must be a good pressure. I have not seen any data on the tolerance to measure the pump housing wear.
Any advice ?
Will post photos tomorrow.