Did the clutch work ok or did it grab a little?
I had the spot welds on my clutch come adrift a few years ago made the clutch grabby and also made some very strange noises but appeared to work fine apart from those issues. When It finally got to the point that it wasn't adjusting properly I pulled the gearbox and found the pushrod snapped and the pop rivets all adrift. I'd check the clutch while your in there. You can see the chatter marks on the clutch plate.