I have recently converted the intake and exhaust system on my '85 300D from a CA emissions version to a fed version. In the begininng it seemed like a fairly simple swap until I tried to install the fed air cleaner. You do need to use the intake & exhaust manifolds, turbo and aircleaner from the fed version in order to make it work properly. The intake & exhaust manifolds, turbo alone are not going to work with the CA air cleaner. It doesn't fit right. The fed air cleaner fits but you need to relocate the A/C lines and the turbo's oil line in order for it to fit right. I still haven't figured out how to install the oil tube that runs from the air cleaner back down to the oil pan so for now I have simply run a rubber line to an old oil bottle for it. It hasn't collected much oil yet. It seems there are many differences between the two models beyond just the intake & exhaust manifolds, turbo and aircleaner. I managed to get everything to fit by bending and rerouting the A/C lines but the entire job was a big PITA. I do have more power and better fuel economy now and plus I am rid of the oxidizing catalyst plus now I won't have to shell out the $30+ for the air filters and there seems to be much more room under the hood.
Would I do it again if I got a another '85 CA model?
Probably not.

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DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012