AU BTR transmission into AUII: Will it work?

[TragicAUII]

The old trans in my AUII has lost gears, or slips in normal driving. Not bad, I suppose for a 417000 km tour of duty.
I got a working trans from an AU that was running well (and no leaks, unlike mine), and now that I'm going to install it, I see there are some differences in the bellhousing (at least).

My daughter noticed the different bolt pattern, as indicated, and the whole in the centre of the drive shaft.

Will it cause any problems?

Was going to swap bellhousings, but no socket that fits the Torx head bolts, and I need the car for work tomorrow.

All help appreciated.
Les