Steering: how much fluid does the system contain? 2001 Gen3.

My 2001 Jumny's steering box leaks. Not the pump, not the hoses etc. It's the s/box. I'm going to try my luck with Leak Lock: try to stop the leaking from the steering box. I have used Leak Lock in other cars in the past, all successful. 
But you cannot pour a complete bottle of Leak Lock into the fluid's reservoir. Only a certain percentage of the total fluid inside. Hence the question:

How much fluid does the PAS system contain when it's full?

Thanks in advance

Menno