97 Supreme speedometer buried

It started last week after adding freon to the a/c. Car started normally after work, started my 35 mile commute home. I noticed at a stoplight that the turn signal was VERY slow. SES light had been on for the pintle position code. ABS light on for RF sensor, replaced hub earlier but light still on. Anyway, I get home, park, daughter goes to leave 2 hours later & interior lighta won't even come on. When I tried to start it, I noticed tach & speedo jumping up & down. Speedo finally wound itself around and never came back to zero. Slow charger 1 1/2 hours didn't help, but jumped it & it fired right off. Overnight on charger brought battery up, so I took alternator to Autozone & it passed all tests. Put it back on, and battery was flat. It was 6 years old, so I replaced it tonight. All seems well, but the speedo is still buried. Its a 97 Cutlass Supreme, 3.1, 120,000 miles. Any help GREATLY appreciated as this is the everyday driver. Thanks in advance !

Okay, I guess it's either so simple that I've overlooked something, or it really threw you folks a curve ? I've done some more searching through the archives, and it looks like some removed the speedometer, cranked it to zero by hand, then reinstalled it. Anybody care to comment ? Also, how tough is it to get the guage cluster out ? Thanks again in advance !