There is -- sort of, though it'll take some parsing of various faqs.
There are a variety of L-jet to Motronic faqs in the Techinical FAQ section at firstfives.org, but they're broken down into various systems (harness, parts req'd, throttle, etc).
Of course you're coming from D-jet, so the upgrade for carbed E9s to L-jet should be req'd reading as well:
http://www.bmwcsregistry.org/Technical/EFIConversion.html
Finally, there is a motronic conversion description for doing a 3.5L engine swap on the SSR, which is sorta helpful:
http://www.seniorsix.org/witandwisdom/petemotronic.html
The firstfives.org stuff will be the most useful, I suspect. HTH.