Since you have two pumps, and they are open center, any valve you add must be in series with the flow from that pump.
You should use a valve with PB to send fluid downstream. You add in the BH valve with PB as the first valve after one of the pumps and feed the other valves downstream using the PB out on the BH valve. The OUT/RETURN port should go to tank.
One pump probably has more GPM's than the other, and the more GPM's you use, the faster things work. You might not want fast, so use the lower GPM pump to feed the BH.
One pump circuit might look like this.
Pump, BH valve , divider circuit, loader valve, then tank.
Other pump circuit might look like this. Pump, remote valve, 3pt, then tank.
Not sure which pump is feeding the power steering, and it might be a divider valve.
Which ever pump you use, leave the divider circuit alone.
If you remove the BH, you will need to couple the tractor unused BH lines together.