Congrats! Lovely machine and most of of us are fans for sure on here, me especially but you are on a 1M thread. We still admire your ride but in terms on information there are lot of big differences between the later 135i like yours with the N55 single turbo motor and the older 1M N54. The steering rack, brakes, rear end, suspension. tire sizes, wheel offsets, etc are all different so you would get better info on the 135i side.
Congrats again, it is really a lovely care and as the cars get bigger, the 1 series is growing more in my heart.
This link will take you to
1 Series site
or if you start at main site, select 1 series and then 1 Series Convertible Forum