Heads up to those that install a 2 bolt aluminum master cylinder.

Thought I'd add my experience since I've got the same Dr. Diff setup as the OP - 13" front / 11.7" rear with 15/16" MC. When I first bench bled the MC there was absolutely no fluid movement out of the rear port until nearly half the piston stroke - the front port had fluid movement immediately when the piston was moved. I contacted Dr. Diff and he sent me another new MC. When I bench bled that one I thought I saw some improvement, but I believe the results were largely similar. Since I admittedly had no previous experience in this area I assumed the fault was mine and went ahead and installed it. This was last summer, and the car still has a ways to go before it will be running. If the ports are truly reversed that would explain a lot - I will be following this thread to see if more information on this comes to light.

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