JD 4020 side console - difference for 3rd remote? ISO style any good?

I'm looking at getting overhauled remotes for my late model 4020 that has all three remotes (later side-console style).  The ones that are on there leak, both externally and internally, and I'm thinking it will be easier and probably about the same cost to just swap on some of the re-manufactured valves I have found online.

 

In my searching around, I've discovered that there is actually a part number difference for the 3rd remote, but I can't tell what the actual differences are.  Can anyone here fill me in?  Is there any way to tell from the outside which is the 3rd valve?  I know I've had them off the back before and I'm not sure I put them all in the same spot when I reinstalled them.

 

Also, the ISO style rebuilt valves are the same price as the original JD style.  Is there any difference in actual performance between the two?  Not having to worry about the adapter tips would be nice, but I've already got them, so it's not a big deal either way.

 

Thanks, Josh

JD 4020 side console - difference for 3rd remote? ISO style any good?