Sort this out please
 

i don't even know what that is ??? axle and rockers maybe?
why would you do that - lug conversion

5 lug conversion... you do that for several reasons. You can get 5 lug wheels for the car as well as upgrade the brakes...

what exactly is confusing? :confused:

you can retrofit to an e30 which have 4-lug hubs/wheels stock. i'd have to check to see if the part numbers truly match up between z3 and 318ti. i'm not sure why the rear hubs/brakes would be any different if it came from a 4-pot z3.

It's a trailing arm and hub--the same one you already have on your car.

This is an upgrade for E30 with a 4-bolt hub. What's the confusing bit?