Fuel pump eccentric problem
Depends on the original application of the cupped washer- I know of at least 3 different depths that were used.
Deepest was on the LA 318/360 roller cam engines. They were the deepest because they used a long snout cam and no fuel pump eccentric.
Middle depth is a "normal" LA motor with long snout cam and a fuel pump eccentric. This is what you will run into 99% of the time.
Shortest is the Magnum cam washer- with no eccentric and a short snout cam, it is nearly flat.
These have to be used per their original application, since using too deep of a washer will cause it to crush when tightened, and possibly not tightening totally and loosening up over time. Too shallow of a washer will not tighten the cam gear to the retaining plate, and could allow the cam to "walk" back and forth and eat your cam.
I'll see if I can get some pictures, but not sure I currently have all 3 different washers at the moment.