I have owned an 83 245T for about 15 years, and in June this year bought a 90 760TI with 193K, but 50K engine, trans, turbo. The 90 760 is basically the same car as your 89, and I think the 245 is close in character (4sp/OD, suspension mods, etc) to the 242.
The 760 is the first autobox I've owned, and it took months for me to be comfortable with it (many adjustments of the kick-down-cable later...) but I have come to appreciate the many creature comforts the 760 has as stock - yes "dull" at first. The 240s will always handle tighter, feel more responsive, and give the impression (at least to me) that I am "wearing" the car, not cramped in it, but that it responds more quickly, precisely, etc. The 760 will remove you to some extent from the driving experience, but its a different car (understatement).

So, here's the part you should ignore. Keep them both. If the body on the 242 is still in good shape, fix it up; tune the 760 and see what happens.

And please don't think I treat my cars like they're sentient - I'm just going out and talk to my 940 - don't want it to feel ignored.

Jim Weiss
have three, want more...