As already suggested, you might be better off converting to chain drive unless you prefer the belt. I've never done it but it's supposed to be a direct swap. I think the chain guard swaps as well but don't quote me on that as it might have different mounting points. I forget.
PS: what belt are you installing? I don't remember if anyone ever found a reasonably priced replacement.
believe me if this latest belt snaps, I'll convert to chain. And no there is no comercially avaialable direct replacement at any price. So far there has been a relatively good supply of used belts but that supply will just be getting smaller each time I replace it. It has gotten to the point that I keep a spare on hand and once used, I start looking for another. So, I just used my last spare and immediately found another on ebay for $45 (plus shipping). It arrived today and looks good. But as @
82KZ305Belt
says, its still a 40 year old belt.
I won't buy another. if this current one snaps, I'll install the spare I just received and start shopping for sprockets to install for next time.