I have some comparison pics of the BJ and 181 lower trailing arm and spindles.

http://forums.aussieveedubbers.com/view ... ?tid=56811

You can see the difference in offset of the spindles from the ball joint centrelines.

You can see how the centres of the balljoints are the same for the BJ and 181 spindles



Standard ball joints, you can see the limited surface area that the lower ball joint(top one in this photo) has to work on.



BJ and 181 lower trailing arms


181 trailing arm has thicker wall thickness, upper BJ trailing arm has same thickness as lower 181 arms


BJ, modified BJ and 181 ball joint socket in lower trailing arm.


This shows the difference in the shock absorber mounts, but the axis and centre line of the shock absorber remain the same. The 181 stud is longer and the boss machined back closer to the ball joint to accommodate the longer sleeve on the 181 shocks. The 181 stud has a larger thread.



I can see no difference in the geometry of the 181 and standard ball joint trailing arms. I have easily modified a lower bj lower trailing arm to accept a 181 ball joint.

i used thing spindles with type1 trailing arms. i just swapped the lowers from side to side and pressed in the thing balljoints from the bottom.
this picture shows type 1 trailing arms on my beam.