I'm pretty sure the 95 E300 did NOT have computer control relative to the amount of fuel delivery and I'm pretty sure the 96 and on E300's did have computer control of fuel delivery in some manner.

This swap would also be complicated by transmission issues, the E300D turbos all used the 722.6 transmission and the drivetrain management software might be a bit confused if it was asked to operate in an environment where it was expected to coordinate activites with a 722.6 transmission that no longer existed.

It would be reasonable to assume that the turbo and non-turbo versions of the OM606 would share the same bellhousing interface but I don't have any first hand experiences with the issue.

Sounds like a fun project.