Mind you: most replacement forks from the enduro and motorcross bikes have 300mm of travel. The fork might need modification, so it won't hit your radiator on full stroke...
And the fork most probably needs another spring/valve setup
and as mentioned you'll probably go back to one disc brake setup, so you'll need a matching master cylinder brake pump.
I would suggest to swap a complete front end:
- forks
- wheel
- master cylinder
- fender
but change/keep:
- fork stem
if you decide to go this route, make sure you do it right