Slave cyl removal?

[Dry Ridge Design]

Got under the car today to replace the slave cylinder  (in 85 4Ksq) and
wasn't able to figure out the fastening to remove it.  Is anyone familiar
with how the clutch slave is removed.  I don't have a Bentley or Haynes
handy and they didn't carry it at the localAP store.

I can find where it is fastened, but not how.  I can stick a small allen
wrnech all the way through the hole where the fastener should be...but there
doesn';t seem to be a nut or anything to turn.  A Pin to pop out?

Any help at all is appreciated..

Stefan Weir
85 4Ksq
82 Diesel Vdub Westy