After mentioning I wanted to upgrade the diff, a belgian friend pointed me to a used G50 LSD, which turned out to be a 996 GT2/3 Motorsport unit with asymmetrical 40%/65% ramps.
To say I was pleased afterwards is an understatement
There is a risk these are well worn and as this one was stored for 5 years. As if I needed any extra persuation to open up a new part
Here you can see the asymmetrical part of the diff in the different ramps where the spider gear is:
These are the friction disks. They are 2.7mm thick and that seems to be a typical value from reading some 911 boards on the matter:
When I took the first cover off, there was quite some 'spring' pressure from the concave ('belleville') washer that sits at both ends, so I think there is some useage left in this unit.
Not sure if I can just put the washers at both ends over and install this as is. Some say you can as this is an original unit and they have all the same measurements, others say you shouldn't.