I am having to redo my water supply to the Bassett T. The last owner had the Ball valve and T valve supplied out of the T Stat housing. I could not get enough pressure due to dual dumps. I do not recommend restricting the dump unless you like buying and installing new head gaskets. I have posted a pic of a Bassett supply line routing below. Your supply to the Ball valve and Bassett T should come in before the gate valve off of the pump.