I found the manual for the splitter online, control of the valve appears to operate exactly as you have described it Lou. There is also a note in there detailing how imperative it is to make sure the pressure line (from tractor) is hooked up to the inlet side of the valve.
Now it seems the biggest challenge for me to determine which remote is activated when I push the lever forward or back, I'm going to have to break out the manual for that.
To me the easiest way would be to look at the splitter and find the correct line to supply the splitter with and mark it well,
then I would remove what ever fitting is on the return line.
Securely tie that line to something substantial and into a bucket,
At the tractor connect the line feeding the splitter into one of your remotes ports,
briefly and gently operate the tractors remote lever in one direction,
if you get flow into the bucket you have the operation for the port you selected and the way you moved the operating lever,
if no flow move the operating lever in the other direction and now you should have flow into the bucket.
(all this is assuming you only have one rear remote on your tractor).
Once you have determined which way to operate your tractors remote to get flow you have to decide if that is the operational method
you desire. If you would rather move the tractors control lever in the other direction for your splitter (it may be easier to bungee it)
then move the splitters supply line to the other tractor port and verify that you get flow with the desire operation.
Mark those connections so as to be able to remember them.
Reconnect your quick coupler to the return line and connect to the open port.
Good luck,
it's some what confusing to write things out that would be so much simpler to just do.