I found this from IslandTractor:
"A diverter valve is one of three options to run a grapple. Cheapest, if you have rear remotes, is just to use the rear remotes. I did that on my first tractor and was very happy with it. Costs only fittings and hose and a few zipties to set up and after measuring and procuring those items you can be grappling in about fifteen minutes. A diverter valve, which I have on my current tractor, is an intermediate solution. I obviously use one and it works but I'm not in love with it. Benefits are that it is a bit less $ than a third function valve and that you can feather the grapple jaw closing. Downside for me is that when I get busy I not infrequently hit the button at the wrong time and dump my grapple load. That is clearly not a major complaint but rather an annoyance. More important to me is that I don't see any particular advantage over the simple rear remote control (so long as the controller is easily reached like the stick shift in 4 on the floor). A third option is the electric over hydraulic (true third function). That will cost $600-900 and offers independent control of the grapple jaw via an on off switch. Benefit is that it is a separate control (compared to diverter) and downside is that you cannot feather the valve (on or off). My advice, if you already have a rear remote, is to simply use it. All the hoses and fittings can be repurposed later as part of a diverter or third function set up if you don't like the rear remote control. And, if you don't already have at least one (preferably at least 2) rear remotes then this is a good time to consider spending that budget on rear remotes that will have multiple uses beyond just grapple control."
Looks like I just need a pair of long hoses....thanks IT!