done some further googling
he used a 4l65e trans and a adaptor kit to a jeep transfer casehttp://www.ls1.com.au/forum/archive/index.php/t-44696.html
Reading up on this the 4l60e is a turd, direct qoute>_________________________________
The 4L60E has 4 pinion planetary's .
The 4L65E has 5 pinion planetary's .
Holden realised the 4L60E has a fundimental flaw .
Under load the input and output shafts can flex between there bushings , causing the driven sungear to move and missalign in the planetary .
If the sungear is missaligned it may only make use of 40% of its contact surface area . This minimal contact breaks the teeth on the planetary ..
So in putting the 5 pinion planetary in the 4L65E trans , even if the sungear moves the extra pinion gear creates more surface contact on the missaligned sungear , increasing surface contact and helping supporting the load .
The 5 pinion planetary is a band-aid fix to strengthen the trans and aid in shaft support .
In my opinion a properly modified 4 pinion 4L60E trans is much stronger than the standard 5 pinion 4L65E transmission .>_________________________________