Just make sure the bottom of the bucket has at least 10 1/8" diameter and you're good to go.
On a side note, of all the things I bought at AG, I'm most disappointed with their bucket. I bought it for almost $13 a while ago thinking that (1) they're the only buckets the grit guard will fit in, and (2) they'd have gallon markers on the side, for measurements. When it arrived, I was disappointed to see there were no markers. To add insult to injury, I find out a couple of days later, my local mom-and-pop home hardware store (my Home Depot didn't carry them) carries a bucket of exactly the same size for only $5, and it comes with a lid. Oh well, live and learn.