dr. diff master cylinder

I have one of each of his MC's. The 1-1/32" came with a large, 'level' sitting reservoir which he later referred to as a truck reservoir. The 15/16" had the smaller, 'tilted' reservoir.

I shimmed the caps on one of them by adding a plastic discs cut from a milk carton between the rubber gasket and cap. It tightened them up and worked fine - that was before I discovered the Dorman option.