Gearbox under refurb - anything essential i should check on?

Hi guys
the work to refurb my 5HP24 gearbox is finally being undertaken by an auto tranny specialist.
They've done this kind of work loads of times before, on the 5HP24 in particular, but maybe not on an 8 Series -- but i really want to know:
1) Anything quirky / unusual about dropping the gearbox on a late model 840 they should know about first?
2) What is the best type of fluid to ensure they use to fill it up once the job done?
3) any other quirky oddities that are 8er-specific that could catch them unawares?
thanks for replies

dear me i do waffle.

The job has been completed - all is well apparently - and I'm going to collect her back on Monday morning.
I can't wait to drive her again after a couple months out of action..

Zitat von reinhard;123128

Fingers crossed that the enjoyment is just like the very first time you saw her

Reinhard this I can take as a given.
I have never repeat never driven the car and just motored along feeling normal.. I enjoy every single 5 minutes, this is what makes the car so truly special for me.

Update:
The gearbox is rebuilt and they've done a good job. Forward clutch pack 'A' (or whatever the correct term is). More precise details were scant.
Ironically after my comment to Reinhard yesterday, I drove home subdued. I think there is a realisation from me that I am on the very edge of my 8er ownership (basically at a crossroads) and its making me more than a little downbeat. But there are worse things life than needing to give up your 8 Series!.. so I must put it in perspective.

I'll take the last question as I can easily answer that - Tired of 'canary' yellow?