This is my daily driver 1980 240D 3.0VNT. Currently at 222k miles on the body and 350k+ on the engine. The OM617.952 is from my old 1982 300TD and I kept the 4-speed manual the 240D came with. I average 27mpg and I have hit 34mpg on highway trips!
Performance modifications include a GT2256V VNT turbo from a 2003 Dodge Sprinter, W115 300D intake manifold, Fram 8038 air filter with 3" ducting to the turbo inlet, rack limiter removed from the injection pump, pyrometer and boost gauges, 15mm rear sway bar, 15" 560SEC wheels and 205/60R15 tires.
Last dyno, before removing the rack limiter, was 107hp and 200lb/ft at the rear wheels.