FarmTrac 675 PTO Synchronising Clutch questions

[MakinDust]

I am hoping someone can tell me where the PTO synchro clutch is, and also if it is the clutch that is activated when the PTO clutch handle is pulled up. I have read the service manual for the FT80 and it has a brief page about this clutch but I cant tell if it is in the PTO housing or the transmission. I found chunks of friction material in one of the hydraulic filters and don't know if it is brake material or if the synchro clutch also has a friction disk in it. I bought this tractor used and the previous owner had issues with the PTO "T" handle and used the PTO clutch to stop the implement rather than fixing the linkage. I have repaired the linkage but need to figure out if I need to replace the clutch(s).