Carb rebuild

[Pmhearns]

I have searched and searched on this forum and others alike but cannot find what I am looking for.

I am fairly new to carburetors, I have basic knowledge and by no means, consider myself educated at all. I am trying to 'clean and rebuild' my son's(17year old) carb off his newly purchased 2000 gz250. Each time we showed up at the guys house, it started up fine and rode but with choke on. After avoutb10 minutes of light riding I realized the carb was still on. I turned it off and it still raneeds fairly well. When I slowed to idle the bikes rpm slowly dropped and at times I had to shift up and let the transmission slow the rpm.

I figured ok, let's clean the carb. Bought an eBay kit(only one I can find unless I buy parts individual) I noticed on partzilla the diagram is different from the service manual. There are 2 rings on the pilot screw and the screw sits too far out for there to be a cover over it. The service manual only says ring and a cover... agsin, there is no cover because the needle sits proud of the orifice in which it sits. So is there only 1 ring or 2??

Lastly, the needle jet seat looks as if someone tried removing it and failed. The upper lip is all chewed up, and I can't figure out how to get that bugger out!

Any help?