To check for worn fork pins rattling apply slight pressure to the fork by the slave push rod? If the rattle stops it's the fork or worn carrier groove or possible wear of gearbox nose o/d to carrier i/d.
Just a thought. FYI mine rattles and don't know what the cause it but it stops when clutch is engaged. I have new gearbox carrier nose, new carrier, new bearing (correct thickness). It's annoying!
Iain