I don't have quiet the list of mods as paochow, but have done some improvements. Respringing the suspension suprised me the most. I'm currently installing the FCR from an E model. I say currently because it has been an on-going project for a month or more.
I rode it today for the first time with it & all I can say is WOW! The difference is night & day for throttle response & snap. However, as I pull it into the driveway, I noticed a real strong gas smell. I look at the carb & the damned thing is leaking from the float bowl.
I disassembled the carb & turns out the float bowl gasket was pinched & seemed to be a little dry rotted. Also, my accelerator pump squirts too long, so I'll order the CRF 450 kit for it. I can't wait to finally get it done. It's a 'dial-a-wheelie' machine with the FCR!!
Here's a link to my garage on TT: