OK, I did a little research on this and there is supposed to a residual valve for the rear drum but not one for the front disc if the Mc is above the calipers and a residual valve for both if the mc is below the calipers. I also learned that if there is a residual valve the fluid will just trickle out of both ports on Mc with the lid off and if no valve it will flow out steady. I tried this on one of the Mc I took off and the fluid came out of both ports at practically the same rate. I guess this means I have the residual valve and need to find one without it.