WOW!! Talk about a hack job!!
CBC, Custom by Cobblecraft, Ya gotta love it.
That unit appears to be or maybe was an adjustable one by the looks of what's left of it.
Anyway, look here.
Are you sure it's BB36 and not a CW36??
https://www.cubcadet.com/equipment/A...0-A/0114300001
You need parts 18 & 22 I believe.
Note: there are 2 types of clutch set-ups depending on your ser#
What is the serial # on your unit?
What Cub are you installing this on??
Mine is on an 'O' and I had to rebuild those 2 parts for mine.