@shinichi
well the duration of the mod really depends on your sanding
kungfu 
i took about roughly an hour to finish up the job, bought the roughest and finest sandpaper available from the hardware store and just sand it, i tried using those stones those auntie used to sharpen their knife too, but that one is of no use, sand paper is the best option, start from the rough then steadily move on to sand it on the finest.
Do remember to rotate every once in awhile when you are sanding as you would not want a unsymmetrical LC-1 right?

You must use force as well, where the chinese are concern its
am lik (canto), u must have the kungfu!
I did not use any cut and sand ways that reader had mentioned, mine is just pure sanding kungfu in action!

here's two shots internal and external of my LC-1.
Will be posting my bag where i put all my stuffs later.
» Click to show Spoiler - click again to hide... «
Hmm feel tempted to sand my LC-1 too... haha but I know I'm not good at doing these kinda things.
Let see how first... if most members here able to do it without any problem I might try my luck...