<p>I just cleaned a Canon FL 200mm F3.5 I got off ebay as a junker.<br>
With some of these old lenses like this the entire front barrel will unscrew off the body of the lens with the front elements intact. Thats the easy part.<br>
My 200mm FL has a single slotted set screw in the side and if you loosen that the entire front assembly unscrews. <br>
I disassembled it from the front down to the aperture, then took the mount off the back and got some of that assembly out of the way and removed the rear group and cleaned the exposed the aperture without removing it.<br>
I really pulled my hair out on this one, because it was difficult to figure out how it came apart. <br>
Just prior I had cleaned a Mamaiya 135mm F2.8 which is easy by comparison and a nice lens and it was much easier to take apart. Similar in that the entire front barrel unscrews. <br>
I did learn one thing. I dont want to work on any Canon FL lenses. <br>
Be cautious if you remove the rear silver ring because apparently some lenses have ball bearings under the ring. Mine did not.<br>
You might want to watch a few of this guys videos. Your lens is not on there, but you might find some useful info.<br>
https://www.youtube.com/channel/UC89vHLITb7DWKe07_hSWYBw</p>