Hoover U6331-930 - Help with belt replacement

[sumitk]

Hi all. Well, it started as a simple project to replace the belt but ended up being a big mess. As I opened the bottom of the Hoover to replace the big belt, the small belt popped out as well. Thats not a problem in itself but the small black wheel that sits on the self-propel pulley also came off. I have no idea which side of this wheel goes in first and neither do I know how to secure it on the long screw that extends out of the self-propel pulley.

I have a non-working Vac right now and I would be greatful for any suggestions. I would hate to pay the vacum shop $40 to fix this old vac.

Thanks in advance.

Regards,
Sumit