So as I was putting the final piece of my CM400 on before closing up the engine (hopefully but probably not for good) I managed to drop it into the crankcase. It was that delightful, tiny retaining pin that keeps the connecting pin from sliding out of the cam chain tensioner. It is minuscule, and it went right down the cam chain gallery. Any ideas on retrieval that don't involve splitting the case? I tried a magnet, but the telescoping pen-type one I have didn't go down there well enough to stick. My next step was going to be draining the oil and going in through the drain and/or filter hole. Any thoughts, tips, or tricks?