Hello , Im Bobby.
Are you sure you have the correct belt? I see there is a SN split so it could be 2 different size belts that it could be.
Well that's what I'm wondering. I got the belt from a Honda dealer. They did NOT have the exact part but they said the belt they gave me was the exact same size. It seems to be looking at the old one. My frame serial is(NNN) NNN-NNNNso from looking on the net (and the dealer agreed) I needed 22432-736-701. It's SB-32 and that's what they gave me. 5/8" I think.
The belt should only get tight when you pull the lever to make the augers turn, So it should be loose when the handle is up .
I would put the housing back together, Unplug the spark plug wire , Then use the pull rope to turn the engine over to help get the belt on the pulley..