The original rubber washers , will most likely be soft and or torn/ damaged, they are not seals, but rather pressure washers, if you look at the design the steel top hat spacers are designed to stop the cam bolt being over tightened, so once they are tight , you can add another 100lbs on pressure on them and they will not clamp the cam cover down anymore, as once the top hat touches the cylinder head thats it they will not get tighter, what happens then is the compressed rubber O rings exerts pressure down on the the cam cover to press the cover down on the main cam seal, which your old soft o ring will not do as well as new ones. Please look at my drawing to see the how the pressure to seal the cam cover is produced from the underside of the fixed length top hat spacer pushing down on the rubber O ring which then pushes down on the cam cover to exerts force downwards to seal the main cam cover, this is done this way to stop people over tightening the cam bolts and damaging the gasket by squishing it too much