If he didn't supply them with your intermediate shaft then how would they know what size to "burnish" the bushing to?
Anyways, grab the mopar performance one that has a hardened shaft with a pinned gear. Only a few dollars more @ Mancini.
http://chucker54.stores.yahoo.net/mopeninmag.html
Then check the fit before you worry. There's a good chance everything will be fine. Just don't assemble the block before you check this as others have mentioned.