MY 97 ELDORADO'S WATER PUMP HOUSING WAS LEAKING SO I REPLACED THE 4 GASKETS BETWEEN THE ENGINE AND THE HOUSING AND I REPLACED THE WATER PUMP MYSELF.(NO LEAKS ANYMORE...AFTER PUTTING EVERYTHING BACK TOGETHER I NOTICE THE TRANSMISSION WONT GO INTO DRIVE OR REVERSE SO I ADDED A QUART OF FLUID BECAUSE THE DIPSTICK WASN'T READING ANY FLUID....AFTER CRANKING THE CAR I PULLED THE STICK FOR THE TRANNY OUT AND FLUID BEGAN TO BUBBLE OUT ALL OVER THE GROUND IT WASN'T HOT IT WAS COOL IN TEMPERATURE (A COUPLE OF QUARTS CAME OUT) WHEN I PULL THE STICK OUT NOW IT SHOWS BEYOUND THE FULL MARK..TRANNY STILL NOT ENGAGING IN REVERSE OR DRIVE....HELP WHAT SHOULD I DO.

 

Perhaps when removing/replacing the coolant crossover housing, you somehow dis-connected the shifter linkage for the trans.
The fluid "burping" out of the trans is most likely due to you overfilling it when you added the fluid.
I would carefully check the shift linkage on the top of the trans first, and go from there.