great, post.
Which other cars use the "bolted small pumpkin" unit? For example, KAAZ do not list a part for the 135i automatic (which shares it's diff with the 130i), although they list a plethora of other models, now if one were to be interchangable...
BMW
MODEL ENGINE GRADE YEAR M/T POSITION NORMAL L.S.D. PLATES PLATE 1.5WAY REMARKS
TYPE SIZE CAM
3 series
E30 6－cyl 325i 85~90 MT/AT REAR OPEN BASIC 12 M DBW3010
4－cyl M3 MT/AT REAR Mechanical BASIC 12 M DBW3010
4－cyl 318is 89~90 MT/AT REAR OPEN BASIC 12 S DBW1810
E36 4－cyl 318is 93~98 MT/AT REAR OPEN BASIC 12 S DBW1810
4－cyl 318ti MT/AT REAR OPEN BASIC 12 S DBW1810
6－cyl M3(3.0) 93~95 MT/AT REAR Mechanical BASIC 12 M DBW3010
E46 6－cyl 328 MT/AT REAR OPEN BASIC 12 M DBW3020
E46 6－cyl M3 MT/AT REAR OPEN BASIC 12 M DBW3020 M1
5 series
E28 6－cyl 525i、535i 81~88 MT/AT REAR OPEN BASIC 12 M DBW3010
E34 6－cyl 525i、535i 88~95 MT/AT REAR OPEN BASIC 12 M DBW3010
Z series
4－cyl Z3Roadster1.8 96~ MT/AT REAR OPEN BASIC 12 S DBW1810
4－cyl Z3Roadster1.9 MT/AT REAR OPEN BASIC 12 S DBW1810
6－cyl Z3Roadster2.8 97~ MT/AT REAR OPEN BASIC 12 M DBW3010
from
http://www.kaazusa.com/lsd_bmw.html