This might sound kinda dumb, but when I shattered a piston skirt in my YZ, I hosed the crankshaft down with WD 40 and picked off all of the little parts that stuck to it. Then I had someone help me turn the whole bike upside down and again hose the crankcase down with WD 40 and then gave the crancase a good blowing out with an air hose while turning the rod and crankshaft assembly. Sounds pretty dumb, but I got all the little pieces out and it worked without splitting the cases. If you do this MAKE SURE that you take your time and get ALL of the parts out!
Madmatt