Steering Rack Leaking

I have a new RMS front end in my 1973 Duster. This includes a Flaming River rack. To date, I have replaced the rack three times all due to leaking. I have also replaced the pump and check valve (to a lower pressure), replaced all the hoses, drained and replaced the fluid. Yesterday we tried a different rack. We started the car, backed it off of the rack, turned the wheel and blew the seals out of the rack. Pressure has been tested both on the bench and in the car at idle - 1750 RPM without any signs of leaking. Once in the car, the leaking begins. OPEN to any - all ideas / suggestions as this is getting out of control.

Have you tested the pressure during turns in the car?