An imposter in the ranks - an M43 project

[DesktopDave]

This picture is very accurate, oddly.  My harmonic balancer looks just like this:  
Belt Drive-Vibration Damper - BMW parts catalog

Here's the lower case, with the front mounting loop protruding out of the inner timing case (#1) and the crank sensor (#11):

 Timing case - BMW parts catalog

[DesktopDave]

Found this thread, with a lot of good information:
http://forums.bimmerforums.com/forum/showthread.php?t=433471

You're going  to be limited to mechanical changes alone here...I'd suggest compensating with larger injectors so the system doesn't lean out at higher RPMs.

There are significant differences in parts within the various generations of the  Motronic system.  The really early Motronic 1.0 Basic system (in my 633CSi, among others) uses two  three-pin crank triggers, then 1.3 (M20 and later M30 motors) switched to a crank/cam pair of  triggers.  The M42's later 1.7 system added a lot more features but appears to  use the same basic setup.  I'm unsure if those wired can easily be  extended though.  They run in a co-axial package to minimize EMI  crosstalk.  The DME sends power to the trigger (5VDC IIRC), receives an  AC signal in return, and provides a floating ground to keep EMI  suppressed.       

Looks like you have the much later BMS46 DME.  That is integrated into the car in a far more significant way.  My M1.3 and the updated M1.7 are not tied into any of the car's systems at all.  They get a pulse from the starter to begin the run routines.  No EWS, no electronic anti-theft, no outputs to ABS/airbags/gauge cluster,etc.  You might want to see if modifying the M47 crank to suit the existing trigger setup is possible.  That'd be the easiest solution, IMHO.