Seppi mulcher being installed on a SK160lc Kobelco excavator

I am in the process of putting a Seppi rotary mulcher on a 02 SL160LC Kobelco Dynamic Acerra S# ym02u0469. I sent my machine and mulcher oil and pressure requirements to SUN Hydraulics and they put me a priority flow valve together with the instructions on where and how to install it. On the mulcher motor itself it has 3-#3/4 lines, the pressure line A. runs to my SUN flow valve, another line B.(case drain) i am running it back to hyd. tank, the 3rd line C. just returns oil from motor( it still has some pressure ). I don't know exactly where to plumb this line to my machine at. Could anyone help me with this? a picture of someone pointing at the location would be wonderful but may not be possible. But a good explanation will help me alot. Just to say this my machine has an unused hammer valve, which i think also is a one way oil flowing circuit. Is it possible to use its fittings at the valve banks to hook my return line? Any help would be appreciated

Seppi mulcher being installed on a SK160lc Kobelco excavator