The shift points might be affected by the ratios of the individual gears in the manual trans...

OK, found my 123 FSM's and this is what I think I read in the charts...

the 123.123 (240d) with the 616.912 engine has the 3.69 rear axle ratio. (PSFred was correct)

For what it is worth it also shows something called 'gradability' with the manual transmission for this combo...

1st gear (slip limit)%(1 in) 35 (2.86)
2nd gear ditto 19 (5.86)
3rd gear ditto 10.5 (9.52)
4th gear ditto 6.5 (15.38)

123.130 (300D) rear axle ratio is 3.46 autotrans

1st gear ditto 41 (2.44)
2nd ditto 37 (2.70)
3rd ditto 15 (6.67)
4th ditto 7.5(13.33)

300 turbos (all) rear axle ratio is 3.07

What these charts actually mean in English I can not explain. Help,somebody?
I typed this neatly as a chart but it posted squished together....