Trouble with oil seal sizing

[DandZ]

I FINALLY got a rear drive shaft from CC AUTO in Coombs, B.C.
Awesome...but, the seal I got from those guys out in Abbotsford is too big? It also has a metal collar on the O.D. which is probably OK but not like the original. The MD number on my oil seal I gave the guy on the phone and he got me:
OIL SEAL 17667 its an SKF box.
My MD number is 731708 on my seal.
What do you think? Its likely the difference between Automatics and Manual drive-shafts??? We have an L300 5-speed.
Help....????? Zoltan