Just got one of these babies. The original one in good condition, would like to do a good cleaning though. I've been doing a little google searching and haven't found many nice simple guides on doing so. Im not really in the position where i can warrant paying for a cla. I also got a 50mm takumar 1.4 , mamiya sekor 35mm 2.8, and smc super takumar 135mm 3.5. Anyone got any advice on getting these crystal clean again? They're all in very good condition.