I'll be watching this one since to understand what you learn.
My 99 Box has a spoiler that generally works ok but has some quirks.

It goes up and down as expected. But sometimes when I start my car the spoiler indicator light on the dash is lit. ...and then goes out after I start driving. The spoiler doesn't visibly change position (e.g. it doesn't appear to go lower after driving).

When I put the spoiler down, it looks like it sits ~1/8" (maybe less?) too high. It's barely noticeable but I'd like to adjust it downward if possible.

This is how it was when I bought the car 18 mos ago. I recently removed the rear bumper while doing some IMS and clutch work and thus had to remove the spoiler as well. The motor assembly, mounting points, etc all seemed OK. Nothing was loose or disconnected. It wasn't clear to me if you can adjust how far down it goes in the lowered position.

One more thing...
 

Those plastic rivets which hold the painted top-piece are a little pesky to remove. I found alternative trim panel retainers at Autozone that work better IMO. They are GM 458780, and press into position. Fit is good, required moderate force to press into position, and they don't seem like they will easily dislodge. The heads are slightly larger, and you can carefully slide a thin pry tool underneath them to get them started and then a larger tool to pop them out if needed in the future. Here are a few pics below of the new pins, the old pins, and the new pins installed.

http://986forum.com/forums/uploads02...1591914527.jpg
http://986forum.com/forums/uploads02...1591914539.jpg
http://986forum.com/forums/uploads02...1591914554.jpg
http://986forum.com/forums/uploads02...1591914572.jpg