Overflow hose clamp - what is this?

Hi guys,
76 KZ400 D3.
I'm slowly trying to find the cause of a major oil leak on my bike and last night as i was looking things over I noticed this thing looks slightly out of place. Parts diagram calls it a overflow hose clamp.
item 24: www.bikebandit.com/oem-parts/1976-kawasa...d/o/m142903#sch40080
Based on that diagram it looks like it is supposed to go in between the cases, not on top? like it is in my picture. It also looks like there aren't two screw holes, just one?

Can someone clarify this so i can eitehr rule it out as the source or investigate further. FYI the view is with the bike on the side stand so it looks a little crooked and it's a view from below the right side side cover looking at the back of the engine.

It just stops the overflow tubes from flopping around. It's nothing critical. There might be a missing screw at the loose end. Is there a hole there for a screw?