That's pretty surprising. That engine has been replaced before.
See if the block has holes for a PTO behind the basket pulley when you get it off.
Oh, when you go to pull the basket pulley, if it's stubborn, Jeff in PA makes a pulley specifically for removing it. It's a worthwhile investment. If you don't use his puller, you can easily damage the pulley trying to get it off if it's stuck.
