In the US market, afaik, only the later turbo 617 engines (84-85's, maybe some 83's) has IP's with the timing port plug (aka RIV port).

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked