Ya you wouldn't use a tee. The flow goes through the open center of the valve when no valve is operating. Everything is in series with open center valve. Flow is continuous through this circuit until you operate one of these valves to do some work with the fluid. Italics are optional components, including how I think you want to hook up both tim's valve kit and the backhoe.
Pump --> flow divider -- > relief valve --> Loader SCV --> OEM 3rd function --> OEM indep mower lift --> PB hose --> Backhoe --> Tim's valve --> PB return port --> Three point lift --> tank