dr. diff master cylinder

I ordered the dr. diff master cylinder 15/16" with the plate adaptor. stops great for my manual disc/drum set up. the master reservoir is slanted forward and when braking nose dives. the fluid dribbles out the vent cap, has anyone used this set up and ran into this? or is there something else that can be done? I e-mailed the dr. diff comp. awaiting e-mail back.. just putting feelers out....