A904 Hard 1-2 Shift and Reverse

I would recommend before you start shotgunning the issue be sure you have an issue.

IMHO go back and adjust the kick down PER THE FACTORY SHOP MANUAL.

THEN run through the diagnostics as outlined in the FSM for shift points and feel

For all you know a previous owner installed a shift kit.

Also what are you comparing to, to determine your shift is too firm.
I've got some reading to do! You are right about the history of the car, you just don't know what has been done to it. But as I stated at the beginning, this car is original, all the mechanicals need refurbishing. Well, I am comparing it to 2nd to 3rd is like butter and don't even realize I am in 3rd gear it is so smooth. 1st-2nd the car shakes, its abrupt and hard. Thank you for pointing me in the right direction all of Y'all.