Pete, Thanks for the info, I knew about the centering and I had my suspicions about the pump pressure being off since it blew my first reseal apart...
My Chiltons manual lists the pump part number for the '63 Lemans as 5691502 and the ones for the full size '63 Pontiac as 5688853, so they carry a different part number...
How do I tell if it is the correct pump and flow control valve for the Tempest/Lemans? Now you have me nervous!!