E92 335i RHD to LHD conversion


May 26, 2020
So I'm in the process of converting my RHD E92 335i into LHD.
I've got some questions around what is easier from a coding perspective.
Here are the unique traits for the RHD / LHD (donor) cars.

LHD (donor)
Comfort access
km/h speedo
Automatic gearbox.

mph speedo
Manual gearbox

The ultimate goal is to combine them into the following:
Comfort access
km/h speedo
Manual gearbox

I don't know how to do this the easiest way.
Obiously I will use the cable harness from the LHD donor to get everything in the correct position. This harness has cables for the iDrive and comfort access, but not the sunroof.
The easiest would probably be to also use all the modules and speedo from the donor car, since they are already coded for iDrive, comfort access (including keys) and km/h speedo. But I don't want the milage to display 16500km.
So the other option is to use all modules and speedo from the RHD car to get the correct milage. I would have to code the comfort access and iDrive however. And also convert the speedometer to km/h if possible. The background is easy to swap, but is it possible to change the scaling? (mph maxes out at 260km/h while the kmh one maxes out at 280km/h).
Is the speedometer scaling coded into the body module, or the speedometer itself? Perhaps another soulution could be to use the RHD module, but reset the LHD speedometer to get the correct milage.

I also have comfort access keys for the LHD, but not the RHD. Is it possible to pair these keys with the RHD car? In what module lies the pairing?

Alot of questions, but I'm grateful if I can get a response to some of them to figure out the easiest way to do this!