FEL Hydraulic Connections

Hey all, first post ever. HELP!
I purchased a used Koyker loader and have installed it on my Ford/NH 1715.
I am more than a bit baffled about the hydraulic connections. The tractor has three ports located on the diverter valve.
Pressure Out
Pressure Return
Sump or Tank
I think I understand operation of diverter valve. Turning CCW enables fluid to flow to Auxillary equip then to 3pt. (which I turn during my attempts)
I have connected it in every combination possible and cannot get proper operation.
My neighbor has a Ford/NH and his is connected to Pressure Out and Pressure Return only. The Ford/NH manual shows the factory FEL with three lines connected listed as above. My FEL valves only have two lines (P&T) like my neighbors. It is an open center. I purchased a power beyond adapter from a Koyker dealer for my FEL valve thinking that this line would connect to power return. Unfortunately it did not fit. (still trying to get proper one) The same power beyond adapter (with a plug inserted) can be used to change the FEL valve to closed center. Could this work and just run lines to pressure out and tank?
Suggestions???
Thanks in Advance Mike1715

Can't help you with this particular issue Mike (as I'm hydraulically impaired) but I can welcome you to the forum.

Welcome to the forums Mike. I can't help either, sorry.
I do have a Kubota with a Kubota loader and there are 3 lines. I could get pics if that would be of any help to you.

Have you hooked up the lines in any configuration yet? If so how does the bucket respond to each way you've hooked it?

connection config

Pressure out _ P (FEL)
Sump or tank _ T nothing works

Pressure out _ P
Pressure return_T Bucket will lift if moving 3pt at same time
roll and dump stuck at continuous dump

Pressure out _ T
Pressure return_P Bucket will lift and go down, each has a middle position when bucket direction will go opposite. will go down or up
roll and dump stuck at continuous dump
Hope i described OK??