I had my NP231 transfer case rebuilt recently. The rear output shaft has the seal then a metal circular plate and a rubber sleeve that attaches to that plate using a hose clamp.

For the life of me, I cannot get that metal plate to stay put. It always comes loose causing the rubber boot to come loose and all this tears up the seal.

How do I get that round metal plate to stay in place?
Is it absolutely necessary or can it be taken off?

Thanks for any help you can give.