Finished the work, and it seems to be working again quite well. This will become an annual maintenance for me now. Basically, I just drained the fluid entirely (well, about 2.5 qts or so), refilled with Dex II Oreilly brand ATF, drove about 5 minutes. Drained it all again, removed the filter this time (and alot more came out from there), refilled with 1 can Trans-X and the rest (about 3 qts) same brand oreilly ATF and put on a new ATF filter. The shifting delay fix wasn't noticeable right away, but after drivining 5-10 miles, parking and retrying, it hasn't delayed since. And that was about 5 days ago. Thanks to all for your help on this one!