MoparNut,
Here is a pic od my OD-833 with the front bearing retainer turned down. If you compare the OD-833 front bearing retainer that you have, yours has the larger retainer still on it. This is the piece that you have to have turned down to fit an older small block bellhousing. Now look at the trans bolt holes for mounting to the bell.
Here is my BigBlock bellhousing with the same matching holes. My small block bellhousing (not pictured) has 2 sets of holes, One set for the standard 833 and also one set for a 3 speed. I also took a picture from that ebay bellhousing that you bought. I see 2 sets of holes too, but I don't see the matching holes to fit your OD-833. Take a look.
From the looks of yours, I think that you got the wrong one.
Rob