Rebuilt A 833 front oil leak

From the factory, IMO, that larger diameter gasket is too thin, and when you torque the tube, it tears the paper.
Furthermore,
From the factory, IMO, there is too much preload on that spring, which makes it less than easy to select reverse.
So, what I do, is get rid of the paper gasket and install a copper or aluminum washer there, several times thicker than the paper. Then I do the same on the little plug to fine tune the preload, to how I like it. All that spring has to do is prevent the shift-rod from falling into or out off reverse, when it's not supposed to. IMO, from the factory, it's easily many times stiffer than it needs to be.
But worse is how much preload is in the actual shifter mechanism, going from Neutral to Reverse. Criminy! But, I hardly ever use reverse anyway, lol. I like me a nice, easy, "snick" going into reverse, like a Ford top-loader.