Couple of gearbox questions

I bought a gearbox bearing set from Siebenrock. Trouble is, a quick look indicates there are 3 bearings the same size with two of them being sealed. Which goes where?
Research has shown up a variety of answers. Lageraider has a neat table that does show location but suggests one is fitted with only one seal without saying which side.

I've mailed Siebenrock, but I'm still awaiting a reply.

Supplementary question - which way up does the roller bearing on the input shaft go, Writing in or out?

Calling MikeyBoy to reception........

The seal on the output shaft faces the gearbox, the intention is to keep the gearbox swarf out of the bearing. Probably wouldnt matter much if you left the other side in. Wouldnt matter where the other one goes, or if you removed the seal, as the other two small bearings bearings are usually the last to go anyway.
My F650 has sealed bearings in the box and on the balance shaft, but the are proper "Sealed Clean" transmission bearings, but no one seems to use transmission bearings in airhead transmissions!

TBH I was expecting more opinions, and for them to all be different as I can find no definitive answer, but thanks Beemerboff for being "The One"

I did ask on an airhead Facebook group and this is the answer I got from a man who builds them for a living.

Your question is totally reasonable, since even the BMW parts fiche is incorrect on this question. Here's the thing: You can use the sealed-two-sides bearings can be used both ends of the cluster shaft and the rear end of the output shaft. The only place you might want an open 6304 bearing is the rear of the input shaft. That location seems to like all the oil flow it can get.
I've had an experimental build gearbox in my R100(fakeS) for over eight years, with fully-sealed bearings on all shafts except the front input roller (not ball) bearing. The gearbox is quiet, smooth, and shifts like butter, oil (change annually when I remember) comes out clear with no metal particles.

The metal particles are still there, it is just that they are not so obvious.
With a open bearing the particles get into the bearing and are rolled out flat, which is what you see glittering in the oil.
This rolling process does the bearing no good, and is the reason unsealed bearings fail faster.
Do a google search on Sealed Clean transmission bearings, or NSK for the full story.
FWIW virtually auto box has these sealed clean bearings and anybody with any knowledge of transmissions would be fully aware of this, so beware of backyard bodgers who pose as transmission experts!

I don't think guy quoted is a backyard bodger.

+ He seems very much in favour of sealed bearings.