I have a bad feeling that the computer on the '90 is connected to the tranny for shift point/gear data, and you most likely will have trouble without that data.
I don't know this for sure, you need to check it out.
Either that, or the neutral safety switch is different, and this WILL give you fits.
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!