Because the factory E-ring is such a hassle, many people weld the slip yoke cap & install a spring to hold the inner shaft in the diff. But I chose to replace the E-ring with a snap ring like CV axles have to keep them in the diff. I bent it from an old spring, and it appears to work, based on several test-fits.
****UPDATE****
I've done this on 3 diffs now, and they all work perfectly - just like a CV axle in a FWD transaxle.

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