I've now done several hillclimbs, some bentsprints and a rally sprint with the Type 9 box. At the moment it's still running stock internals as by request for funding for Quaffe parts has been denied (Silly little things like mortgages).
Is it the best stiffing box I've ever used ?. No - but it's better than the nearly 40 year old Getrag I was using.
Also second gear is slightly taller than the getrag 1.97 versus 2.02 and third is slightly lower 1.37 versus 1.32. Not huge differences I grant you but it does seem to make a difference.
Overall I'm happy with it.
Here are some fitment notes for anyone who's interested
For any one else considering a non BMW gearbox swap, the trick seems to be to start with an automatic bell housing.
I used one from a M10 powered E30 318 and then machined up an adapter plate to go between the bell housing and g'box.
In my case the throw out bearing is a Sierra one, using a modified Sierra clutch fork and E30 slave cylinder. The slave cylinder setup is similar to an E30 although in hindsight it would have been easier but more expensive to use an axial slave cylinder / bearing.
The clutch is a custom 228mm, there's a company in Auckland that can provide you anything you want in terms of diameter and center spline in 24 hours for not too much more than a stock clutch.
The drive shaft is a modified E30 one using a sierra coupling which is somewhat larger than a 2002 one. Also in hindsight I should have considered a one piece drive shaft, the sierra output shaft slides and sits much further back in the car which may of made it feasible.
Tunnel mods were limited to moving the gear stick hole back a bit, some strategic dents and some new mounting points. Again in hindsight about 25mm more height in the tunnel would have been better.
Other notes - the slave cylinder covers the oil fill hole, when I build up a box with quaffe bits I'll see about putting a filler on the other side - oh and a drain plug.