Almost a year later....Looking at the differences per the Bentley Manual, it is not someting I would want to do...but is do-able without tunnel mods....I can't speak for the 328's but I have continued to be impressed by the performance of my 325s automatic. I think if I wanted to go manual I would look at a trade or flip. If someone can fit a Chevy 302 V-8 engine and Transmission into an e-36, anything is do-able!!