Well after checking everything I could that was recommended on a previous thread before buying , I am now officially part of the K5 Brotherhood.
The bike is a 92 after checking the VIN as well as the engine codes.
Since I was on leave, I didn't have time to go to deep into taking things apart to find out what all was inside, here is what I do know.
Engine: PSI Porting and Rad Valve installed. No spacer was installed.
I pulled the ignition cover and could not feel any play when trying to move the flywheel. No fly wheel weight has been added.
Pipes: PSI installed and he gave me another one that is an FMF Fatty. I called FMF and with the part number that is on the pipe, it is an original Fatty that I guess they no longer make.
CARB: looks stock but I know I will need to clean it up good and do some jetting to get it spot on. The good thing is, the bike starts on 1-3 kicks when cold and 1st kick after warm, but runs a little rough off the bottom. Once "on the pipe" it runs great. Air filter was clean and fresh.
Shock: not sure if any work had been done to it, but it does have a dual Eibach spring setup. The big spring is black and there is a short (2-3 coils) blue spring on top of it.
Forks: Didn't tear into them so I don't know what spring are in there, but there was no oil leaking out of the seals even after over an hour of riding the bike. Spring rate seems to be pretty close for my wieght, at least from the riding I got to do. Kind like the way the blue forks look after I finally saw the bike in person for the firt time.
Chain: Regina (non O-ring) Fredette (?) chain guide.
Sprockets: Front looks stock (13T) Rear is a Talon (47T) Both have lots of life left on them.
Brakes: Both function well with the rear rotor looking stock, but the front looks different that the ones I have seen on most pictures of 92 K5s.
Tires were pretty new Dunlop 742s Not the greatest tire from what I have read, but they stick pretty well on the dried grass in my field.
Bars are low profile non cross bar type. Can't remember exactly if they were Easton or Renthal (Whatever company uses the "100%), but they fit me well, and were a comfortable bend.
I did find the suspect cracks in the upper shock mounts, but my son is a welder and said he could fix that with no problems.
No wobble in the either wheels or the swing arm. The suspension travel is smooth with no sticking points and trackes true even over the bumpy ground of my field at speed.
It seems to turn great even on grass. So I guess the guy who had it set everything up for motocross (which is what I plan to do with it.)
Overall, I think it is a great bike that just needs a little more love and attention.
Smoke from the long trip back to Afghanistan, but if there is anything else I can remeber when my brain gets back to normal, I'll post it.
Bottom line...I love my KX 500!!!!!!!!!!
Thanks to all who gave me some help in looking the bike over before I bought it and thanks to this site for all the great info everyone has shared!