CSL were a Japanese guitar maker back in the 1970's who were among many pioneering the manufacture of cheap copies of American and European Instruments. I've been using this Maccaferri copy as my main acoustic for as long as I can remember and as such it has been quite bashed around. Most notably, three of the cheap plastic tuning keys had been smashed. Out of cheapness/laziness I'd only temporarily replaced these with any old replacement knobs that came to hand. Now, in my semi-retirement I thought the time had come to fit replacement machine heads. I'd found some going cheap on a Chinese website (US$8.99) which seemed to fit the bill so after checking the distance between each pin was correct, I ordered a pair of rectangular heads with exposed gears.
First I removed the old strings and inspected the fretboard. Whereas it looks like a rosewood neck I will precede with caution in case it is stained or painted to disguise a cheaper wood. Certainly it was very dirty, having not been cleaned for many years. I rubbed down the fretboard with fine wire wool then dressed with lemon oil from the Jim Dunlop Guitar Tech Care Kit.
Then I removed the old machine heads and cleaned the wood underneath, which had been hidden for almost half a century!
I test fitted the new machine heads but they wouldn't go through the original holes. So I measured up and the new poles needed a 12mm hole. Fortunately I had a large enough drill bit, and drilled each hole. After that I was able to fit both machine heads no problem - even the old screw holes lined up. Job done in under an hour.