Well, with the eBay unit, you may be getting only what you paid for. An Auburn or DTT usually runs $480-$600, IIRC. Installation may be another $300??? Are you sure there is no reference to "anti-spin..."?
Yeah i read it upside down and backwards. The one on ebay is a dana spicer that looks just like the one in my SST. When I get home I'm going to pull off the diff cover, look at it and give it an oil change. There won't be any confusion after that, thanx for quik reply.