It was brought to my attention a 300 swap into a 240D I'm looking at is fairly easy.
So I'd probably want lower axle ratio to go with it.
I found this:
230,240D RATIO 3.69:1
280E RATIO 3.58:1
300D RATIO 3.46:1
300DT 85 RATIO 2.88:1
300DT TO 84 RATIO 3.07:1
So what's going to be best?