there is a capsule inside the IP that controls the fuel delivery to the engine fuel curve the IP was intended to work on. Not sure if that was clear but its a different part for the 3l and the 3.5l engines.
I kept the IP off my 350SD that went to MB heaven and a friend who works on Bosch pumps changed the capsule in it for my 603. It works pefectly with no smoke and good fuel economy. At the same time he set the governor up to match my 3l.
If you have a shop that works on Bosch IP's I may be able to find the part, ie "capsule" for you or a part# at least if you wanted to do it right.
DDH

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