I can help with a couple of things.
If you 99 GT is like mine with the low-tech driver information center, there is no reset oil life button. That's on the step up from ours. To reset mine, I have to turn the key on to "run" (with the engine off) and press and hold the accelerator 3 times within about 6 seconds or so. Make sure to hold the pedal down for about 1 full second. I found it takes a delicate touch to get the timing right. Have to try a bunch of times before the light finally the light does the "quick flash" to let you know it has got your message.
On your key fob range, some folks suggest touching the fob to your chin. Strange, but it seems to help. 20 feet is actually pretty good range
Speakers - two in the rear deck, two in the lower doors, and two mini-tweeters on the door near the A pillar.
My rear doors rattle when I shut them. I spent a couple of hours with the inner panels off trying to locate the source. I found that the lock actuator rod was the culprit. That cured it for then - but now a year later - they are starting again.
That's all I can help with, other than to feel your pain of paint chips. I have more chips in my hood that I want to admit to. I look at that as my excuse to get a RAM air hood someday. It has to be painted then anyways....