Ohlins 1304
Viscosity 11cST@40C
http://www.peterverdone.com/wiki/ind...spension_Fluid
Take your pick from what's available, using the table in the link above. I'd go with a synthetic fluid between 11 and 16cSt@40, and a viscosity index of at least 200 (low VI will tend to fade when used hard and temps increase).
You'll notice some brands may be 2.5wt, others 5wt.. some may be labelled shock fluid, some suspension, and some tuners will even use fork fluids if the specs are up to it. IE motorex racing fork oil 2.5wt (15.1cSt@40C VI 200).
In regards to the rebound adjuster wheel, it won't click until the shock is assembled and pressurised. You need to ensure the adjuster is OPEN before you discharge, or if not you may need to physically push the rebound needle down inside the shock shaft to allow fluid to pass during the bleed process.