I am helping my friend with some research. He has a 300D with an automatic tranny. He was told there is a slot where you can insert a flathead screwdriver to modify the shifting. Where is this slot located? I think the car is a 84. Any help would be greatly appreciated. E-mail me at david.hofman@cox.net

probably talking about the modulator valve. You can tone down how hard the transmission shifts by turning out about 1/2 turn(I think it's out, maybe in)and driving it to see how you like it. It's just a trial and error thing and a little bit of driver preference. the modulator valve is probably either red or green on that car so it's easy to spot on the side of the tranny.

You can pop that red or green cap off and underneath you will find a "T" shaped metal tab in most cases.
Turning the tab clockwise will harden the shift points, but do try small increments of adjustments at a time. The red or green cover has slots around the "ID" that holds the metal tab in place.

just remember when you adjust that for softer shifts, you ARE making the trans slip, so do it in moderation.