No, for the 200x you have to use 83-85 200x rear fenders and seat and tank. Also if you want to put the 185s engine into the 200x, you will need to mod a rear brake pedal since on the 200x the brake pedal attaches to the side of the engine. The quick and easy way would be to just keep the stock front end and find a wheel and tire. To fit a 200x front end on, you would have to change over the steering stem to the 185 steering stem. There was a thread on here before the switch over describing what to do. Even if you put the 83 185s suspension front end on or the 84 and later 200s, you will still have to mess with the steering stops.
Nicholson 500x (Project)
Nicholson 185s
Nicholson 110 (That takes an atc70 tank)
Ascott 500 head/350x (Project)
Homebuilt Racer Chromoly Suspension 110 (Ragin Runt)
PK Racing Suspension 70
A+ Inc Suspension 70
AWS Aluminum 90 frame
Hi Performance ATC Suspension frame rd350
Hi Performance ATC Suspension frame 90