Gdubb,
Mine is an 87 model. I paid about $300.00 to much for my bike. I also paided $1000.00 but mine was a total basket case. I have alway rode atv's and my son has been riding a 50cc dirt bike for about year a few months. I bought the bike so i could help my son start learning how to ride. This was my first dirt bike and it took only 30 seconds of cracking the throttle to get me hooked. If I had it to do over again I would like to have bought a 88 or new 500. Parts are easier to find. I would go through the whole bike for inspection. Wheel bearings, swing arm bearing, lower link bearings, lower and upper shock bearings,chain and sprockets, steering stem bearings,these are high wear items. Plactic parts are not bad for price. Try to use UFO Plast for your replacement plastic parts. They have factory looking molding. everything you need to do to the bike will not happen overnight. I have been riding and working on my bike sents last May of 2004. One thing I can say is that I have learned alot about dirt bikes from rebuilding mine. Just work alittle on improving your bike each month. Look under A.Hughes 87 KX500 Gallery. Have fun.
Here are some good resources for parts
denniskirk.com
rockymountainmc.com
allballsracing.com They have all your bearings you will need.
monkeybuttparts.com
I have pretty much rebuilt my bike with these guy's.