42RH in 68 Dart advice/request
Yes the fluid passages use a new billet plate. Where your ~1.5”x2.5” plate that states 22XODLU is is where the Transbrake solenoid would go which. Call cope and ask for the Transbrake plate and solenoid. All that is is a fluid passage and with a solenoid in place your blocking fluid to that circuit until you open the valve by pressing the button. Here is my valvebody for reference