OK I went ahead and did it. I drained it all out (incl. converter) and replaced the filter. I added 12 quarts of Mercon V.
I also upgraded the MLPS while I was under there. I have some observations and some questions.
1. The 1-2 shift is now MUCH softer.
2. Reverse engagement is more delayed than before.
3. 3-4 shudder seems to be gone.
4. 3-4 flare has not happened again but that was intermittent to begin with.
1. The MLPS came with instructions that implied I had to do some rewiring. I seemed to have the correct plug already. I believe the rewiring might have only been for earlier years. (I have 1994 LX 4R70W)
2. The MLPS instructions said to choose the "appropriate spacers" It came with 4mm and 8 mm spacers. My old unit had no spacers and the new "seemed" to not need spacers. I did not use either. Have I created a problem?