Installing New Drive Belt on Honda Elite 80

[Scoot_4_20]

Can anyone tell me how? I took the rear part off the shaft and haven't been able to get it back on yet. Do I put the thing back on the shaft before trying to get the belt on, or put the belt on before trying to get that thing back on the shaft?

 

[Scoot_4_20]

Another question while I'm at it :

Do I need to have a new gasket for the final drive cover? Someone online said I could use some gasket stuff from a parts store instead.

I could not get the final drive oil changed yet - couldn't get the tranny cover off for some reason. Oil looked fairly clean in the fill hole. I may get a vacuum pump and be able to pump it out of there.

Manual says it only needs to be changed every 10,000 miles of so but someone online said to change it once a year, which may be OK if I can pump it out of there.